diff --git a/applications/utilities/mesh/manipulation/setSet/setSet.C b/applications/utilities/mesh/manipulation/setSet/setSet.C
index bc800b920aee19d401b79881caa4a5a4d8de8e14..fa48186c90c275c9e013fa709c0ea2831858e110 100644
--- a/applications/utilities/mesh/manipulation/setSet/setSet.C
+++ b/applications/utilities/mesh/manipulation/setSet/setSet.C
@@ -132,9 +132,9 @@ void printHelp(Ostream& os)
         << "    clear           - clears the set" << nl
         << "    invert          - inverts the set" << nl
         << "    remove          - remove the set" << nl
-        << "    new <source>    - sets to set to the source set" << nl
+        << "    new <source>    - use all elements from the source set" << nl
         << "    add <source>    - adds all elements from the source set" << nl
-        << "    delete <source> - deletes      ,," << nl
+        << "    subtract <source> - subtract the source set elements" << nl
         << "    subset <source> - combines current set with the source set"
         << nl
         << nl
diff --git a/applications/utilities/mesh/manipulation/topoSet/topoSet.C b/applications/utilities/mesh/manipulation/topoSet/topoSet.C
index f08ea7516908b193a27045bae629c8170b8abac3..a9cd056c58f8817cc2062ee2210cd752834a8011 100644
--- a/applications/utilities/mesh/manipulation/topoSet/topoSet.C
+++ b/applications/utilities/mesh/manipulation/topoSet/topoSet.C
@@ -247,8 +247,8 @@ int main(int argc, char *argv[])
             autoPtr<topoSet> currentSet;
             if
             (
-                (action == topoSetSource::NEW)
-             || (action == topoSetSource::CLEAR)
+                action == topoSetSource::NEW
+             || action == topoSetSource::CLEAR
             )
             {
                 currentSet = topoSet::New(setType, mesh, setName, 10000);
@@ -281,7 +281,7 @@ int main(int argc, char *argv[])
             {
                 case topoSetSource::NEW:
                 case topoSetSource::ADD:
-                case topoSetSource::DELETE:
+                case topoSetSource::SUBTRACT:
                 {
                     const word sourceName(dict.get<word>("source"));
 
diff --git a/src/dynamicMesh/motionSmoother/badQualityToCell/badQualityToCell.C b/src/dynamicMesh/motionSmoother/badQualityToCell/badQualityToCell.C
index 81788a570355cd8f3f0e4f7bc4464fe8d29cf8b3..1284127080656d0d129a9309d3f27323f63883b5 100644
--- a/src/dynamicMesh/motionSmoother/badQualityToCell/badQualityToCell.C
+++ b/src/dynamicMesh/motionSmoother/badQualityToCell/badQualityToCell.C
@@ -114,12 +114,12 @@ void Foam::badQualityToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding bad-quality cells" << endl;
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing bad-quality cells" << endl;
         combine(set, false);
diff --git a/src/dynamicMesh/motionSmoother/badQualityToFace/badQualityToFace.C b/src/dynamicMesh/motionSmoother/badQualityToFace/badQualityToFace.C
index d98621d52456c3a6db3adf811101e0f8355f9875..1b7ee0d2ac671a068c24ac0c7a80e83880dc854f 100644
--- a/src/dynamicMesh/motionSmoother/badQualityToFace/badQualityToFace.C
+++ b/src/dynamicMesh/motionSmoother/badQualityToFace/badQualityToFace.C
@@ -110,12 +110,12 @@ void Foam::badQualityToFace::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding bad-quality faces" << endl;
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing bad-quality faces" << endl;
         combine(set, false);
diff --git a/src/meshTools/sets/cellSources/boxToCell/boxToCell.C b/src/meshTools/sets/cellSources/boxToCell/boxToCell.C
index 5d4b7bcd4cb7f0e9f3730071086abd950216e1ab..b403151a5905c233346fd213ec95b2235566fa89 100644
--- a/src/meshTools/sets/cellSources/boxToCell/boxToCell.C
+++ b/src/meshTools/sets/cellSources/boxToCell/boxToCell.C
@@ -142,15 +142,15 @@ void Foam::boxToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
-        Info<< "    Adding cells with center within boxes " << bbs_ << endl;
+        Info<< "    Adding cells with centre within boxes " << bbs_ << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
-        Info<< "    Removing cells with center within boxes " << bbs_ << endl;
+        Info<< "    Removing cells with centre within boxes " << bbs_ << endl;
 
         combine(set, false);
     }
diff --git a/src/meshTools/sets/cellSources/cellToCell/cellToCell.C b/src/meshTools/sets/cellSources/cellToCell/cellToCell.C
index 565ad65e34231bfff901d43a15638158b6c8193a..aa23317c567fc4a2d4f7987889d654f3dc47c5e6 100644
--- a/src/meshTools/sets/cellSources/cellToCell/cellToCell.C
+++ b/src/meshTools/sets/cellSources/cellToCell/cellToCell.C
@@ -94,7 +94,7 @@ void Foam::cellToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::ADD) || (action == topoSetSource::NEW))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding all elements of cellSet " << setName_ << " ..."
             << endl;
@@ -104,7 +104,7 @@ void Foam::cellToCell::applyToSet
 
         set.addSet(loadedSet);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing all elements of cellSet " << setName_ << " ..."
             << endl;
@@ -112,7 +112,7 @@ void Foam::cellToCell::applyToSet
         // Load the set
         cellSet loadedSet(mesh_, setName_);
 
-        set.deleteSet(loadedSet);
+        set.subtractSet(loadedSet);
     }
 }
 
diff --git a/src/meshTools/sets/cellSources/cylinderAnnulusToCell/cylinderAnnulusToCell.C b/src/meshTools/sets/cellSources/cylinderAnnulusToCell/cylinderAnnulusToCell.C
index 033b7602ce46b44d30d85f2862be13ae2a5d6335..4cb8e1bfed3b8fe177c8c4a0f4fbe56629d490f7 100644
--- a/src/meshTools/sets/cellSources/cylinderAnnulusToCell/cylinderAnnulusToCell.C
+++ b/src/meshTools/sets/cellSources/cylinderAnnulusToCell/cylinderAnnulusToCell.C
@@ -158,7 +158,7 @@ void Foam::cylinderAnnulusToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding cells with centre within cylinder annulus,"
             << " with p1 = "
@@ -168,7 +168,7 @@ void Foam::cylinderAnnulusToCell::applyToSet
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing cells with centre within cylinder annulus,"
             << " with p1 = "
diff --git a/src/meshTools/sets/cellSources/cylinderToCell/cylinderToCell.C b/src/meshTools/sets/cellSources/cylinderToCell/cylinderToCell.C
index 910868d1717ed1f7943b193e9822b4d8556b58cc..7eb50853a6cae3a92ca277392774fcb9984cf36b 100644
--- a/src/meshTools/sets/cellSources/cylinderToCell/cylinderToCell.C
+++ b/src/meshTools/sets/cellSources/cylinderToCell/cylinderToCell.C
@@ -142,7 +142,7 @@ void Foam::cylinderToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding cells with centre within cylinder, with p1 = "
             << point1_ << ", p2 = " << point2_ << ", radius = " << radius_
@@ -150,7 +150,7 @@ void Foam::cylinderToCell::applyToSet
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing cells with centre within cylinder, with p1 = "
             << point1_ << ", p2 = " << point2_ << ", radius = " << radius_
diff --git a/src/meshTools/sets/cellSources/faceToCell/faceToCell.C b/src/meshTools/sets/cellSources/faceToCell/faceToCell.C
index 5966d80fa26b9ca91d678a407d861ed3d942f5d7..8d7d136530782a2150bc3788d35a4894088def2b 100644
--- a/src/meshTools/sets/cellSources/faceToCell/faceToCell.C
+++ b/src/meshTools/sets/cellSources/faceToCell/faceToCell.C
@@ -176,14 +176,14 @@ void Foam::faceToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding cells according to faceSet " << setName_
             << " ..." << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing cells according to faceSet " << setName_
             << " ..." << endl;
diff --git a/src/meshTools/sets/cellSources/faceZoneToCell/faceZoneToCell.C b/src/meshTools/sets/cellSources/faceZoneToCell/faceZoneToCell.C
index 8079cd72d0c9e8e6d97777c27a2c199272c5a742..9d50ffa689bfddc623ceb684eaa3bb037d9c00a2 100644
--- a/src/meshTools/sets/cellSources/faceZoneToCell/faceZoneToCell.C
+++ b/src/meshTools/sets/cellSources/faceZoneToCell/faceZoneToCell.C
@@ -159,7 +159,7 @@ void Foam::faceZoneToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding all " << faceActionNames_[option_]
             << " cells of face zones "
@@ -167,7 +167,7 @@ void Foam::faceZoneToCell::applyToSet
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing all " << faceActionNames_[option_]
             << " cells of face zones "
diff --git a/src/meshTools/sets/cellSources/fieldToCell/fieldToCell.C b/src/meshTools/sets/cellSources/fieldToCell/fieldToCell.C
index c12bbab2c48fda34682fb86b3eb135202ee6da18..cf57936c72842b5b0eb1bcde21f4029d072e53a2 100644
--- a/src/meshTools/sets/cellSources/fieldToCell/fieldToCell.C
+++ b/src/meshTools/sets/cellSources/fieldToCell/fieldToCell.C
@@ -74,10 +74,9 @@ void Foam::fieldToCell::applyToSet
     topoSet& set
 ) const
 {
-    Info<< "    Field min:" << min(field)
-        << " max:" << max(field) << endl;
+    Info<< "    Field min:" << min(field) << " max:" << max(field) << endl;
 
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding all cells with value of field " << fieldName_
             << " within range " << min_ << ".." << max_ << endl;
@@ -86,11 +85,11 @@ void Foam::fieldToCell::applyToSet
         {
             if (field[celli] >= min_ && field[celli] <= max_)
             {
-                set.insert(celli);
+                set.set(celli);
             }
         }
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing all cells with value of field " << fieldName_
             << " within range " << min_ << ".." << max_ << endl;
@@ -99,7 +98,7 @@ void Foam::fieldToCell::applyToSet
         {
             if (field[celli] >= min_ && field[celli] <= max_)
             {
-                set.erase(celli);
+                set.unset(celli);
             }
         }
     }
diff --git a/src/meshTools/sets/cellSources/labelToCell/labelToCell.C b/src/meshTools/sets/cellSources/labelToCell/labelToCell.C
index a314644f5e3429f25973ca90af0941de9e101543..5828a2ba81324289c55de87b565093ba7e110033 100644
--- a/src/meshTools/sets/cellSources/labelToCell/labelToCell.C
+++ b/src/meshTools/sets/cellSources/labelToCell/labelToCell.C
@@ -116,13 +116,13 @@ void Foam::labelToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding cells mentioned in dictionary" << " ..." << endl;
 
         addOrDelete(set, labels_, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing cells mentioned in dictionary" << " ..." << endl;
 
diff --git a/src/meshTools/sets/cellSources/nbrToCell/nbrToCell.C b/src/meshTools/sets/cellSources/nbrToCell/nbrToCell.C
index 7201163abc781466dc6693d9ced5b927db47a801..4a62f60f723849981ee2911db3301a4ab189a2db 100644
--- a/src/meshTools/sets/cellSources/nbrToCell/nbrToCell.C
+++ b/src/meshTools/sets/cellSources/nbrToCell/nbrToCell.C
@@ -151,14 +151,14 @@ void Foam::nbrToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding cells with only " << minNbrs_ << " or less"
                 " neighbouring cells" << " ..." << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing cells with only " << minNbrs_ << " or less"
                 " neighbouring cells" << " ..." << endl;
diff --git a/src/meshTools/sets/cellSources/nearestToCell/nearestToCell.C b/src/meshTools/sets/cellSources/nearestToCell/nearestToCell.C
index 1894e5ec82578ea63742f81b0ba6c162ba78a7a6..924de4ca6dda0fdb0b4e8d91b225b067d1c748e8 100644
--- a/src/meshTools/sets/cellSources/nearestToCell/nearestToCell.C
+++ b/src/meshTools/sets/cellSources/nearestToCell/nearestToCell.C
@@ -152,13 +152,13 @@ void Foam::nearestToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding cells nearest to " << points_ << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing cells nearest to " << points_ << endl;
 
diff --git a/src/meshTools/sets/cellSources/pointToCell/pointToCell.C b/src/meshTools/sets/cellSources/pointToCell/pointToCell.C
index 03fa90f1139ea96992d0373adc1fb849628d26c8..26e0a619f14c1d85cb5bf736475d19f3a94a9070 100644
--- a/src/meshTools/sets/cellSources/pointToCell/pointToCell.C
+++ b/src/meshTools/sets/cellSources/pointToCell/pointToCell.C
@@ -159,14 +159,14 @@ void Foam::pointToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding cells according to pointSet " << setName_
             << " ..." << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing cells according to pointSet " << setName_
             << " ..." << endl;
diff --git a/src/meshTools/sets/cellSources/regionToCell/regionToCell.C b/src/meshTools/sets/cellSources/regionToCell/regionToCell.C
index 4d5b22b4c247d3ca07fbc8133c1216a87dfa4f4d..10df22acf0f70282a0a5a0cf0f188d98c083fed5 100644
--- a/src/meshTools/sets/cellSources/regionToCell/regionToCell.C
+++ b/src/meshTools/sets/cellSources/regionToCell/regionToCell.C
@@ -432,14 +432,14 @@ void Foam::regionToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding all cells of connected region containing points "
             << insidePoints_ << " ..." << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing all cells of connected region containing points "
             << insidePoints_ << " ..." << endl;
diff --git a/src/meshTools/sets/cellSources/rotatedBoxToCell/rotatedBoxToCell.C b/src/meshTools/sets/cellSources/rotatedBoxToCell/rotatedBoxToCell.C
index db7cde1c758dbbbc9c2fd90d2c9c56aecd51cf01..f4c8216e691323051c017f05f2f44fbdfb1a94d6 100644
--- a/src/meshTools/sets/cellSources/rotatedBoxToCell/rotatedBoxToCell.C
+++ b/src/meshTools/sets/cellSources/rotatedBoxToCell/rotatedBoxToCell.C
@@ -176,15 +176,15 @@ void Foam::rotatedBoxToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
-        Info<< "    Adding cells with center within rotated box " << endl;
+        Info<< "    Adding cells with centre within rotated box " << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
-        Info<< "    Removing cells with center within rotated box " << endl;
+        Info<< "    Removing cells with centre within rotated box " << endl;
 
         combine(set, false);
     }
diff --git a/src/meshTools/sets/cellSources/shapeToCell/shapeToCell.C b/src/meshTools/sets/cellSources/shapeToCell/shapeToCell.C
index 5bdbe838e6c9fcbf30df5dc6c53e186a7bf1414d..9fda5ad9adadda964890ce90058ca93af801e0f3 100644
--- a/src/meshTools/sets/cellSources/shapeToCell/shapeToCell.C
+++ b/src/meshTools/sets/cellSources/shapeToCell/shapeToCell.C
@@ -142,13 +142,13 @@ void Foam::shapeToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding all cells of type " << type_ << " ..." << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing all cells of type " << type_ << " ..." << endl;
 
diff --git a/src/meshTools/sets/cellSources/sphereToCell/sphereToCell.C b/src/meshTools/sets/cellSources/sphereToCell/sphereToCell.C
index c79625b6277c513fa438b6470add2b34d64ab777..0c164dc714a62a998d9aa89887604f85a1d47c6b 100644
--- a/src/meshTools/sets/cellSources/sphereToCell/sphereToCell.C
+++ b/src/meshTools/sets/cellSources/sphereToCell/sphereToCell.C
@@ -129,14 +129,14 @@ void Foam::sphereToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding cells within a sphere with centre = "
             << origin_ << " and radius = " << radius_ << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing cells within a sphere with centre = "
             << origin_ << " and radius = " << radius_ << endl;
diff --git a/src/meshTools/sets/cellSources/surfaceToCell/surfaceToCell.C b/src/meshTools/sets/cellSources/surfaceToCell/surfaceToCell.C
index 04cd8842e1bce1e03151647d14d9525f8ac1a35d..5723b9962c7689aa54b08bf5c50528b9b56e42c4 100644
--- a/src/meshTools/sets/cellSources/surfaceToCell/surfaceToCell.C
+++ b/src/meshTools/sets/cellSources/surfaceToCell/surfaceToCell.C
@@ -487,14 +487,14 @@ void Foam::surfaceToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding cells in relation to surface " << surfName_
             << " ..." << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing cells in relation to surface " << surfName_
             << " ..." << endl;
diff --git a/src/meshTools/sets/cellSources/targetVolumeToCell/targetVolumeToCell.C b/src/meshTools/sets/cellSources/targetVolumeToCell/targetVolumeToCell.C
index bf34accc7feadc30a88d50cfc40cca693205ae3e..12862a2adaf605ff59d2320aa6c3a37e944d0cb4 100644
--- a/src/meshTools/sets/cellSources/targetVolumeToCell/targetVolumeToCell.C
+++ b/src/meshTools/sets/cellSources/targetVolumeToCell/targetVolumeToCell.C
@@ -327,14 +327,14 @@ void Foam::targetVolumeToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding cells up to target volume " << vol_
             << " out of total volume " << gSum(mesh_.cellVolumes()) << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing cells up to target volume " << vol_
             << " out of total volume " << gSum(mesh_.cellVolumes()) << endl;
diff --git a/src/meshTools/sets/cellSources/zoneToCell/zoneToCell.C b/src/meshTools/sets/cellSources/zoneToCell/zoneToCell.C
index 81959a589b83afd4ad2ce6016d72cace9505b92d..16003df577e43ca156f7ae74c1dcebf6d7277438 100644
--- a/src/meshTools/sets/cellSources/zoneToCell/zoneToCell.C
+++ b/src/meshTools/sets/cellSources/zoneToCell/zoneToCell.C
@@ -152,14 +152,14 @@ void Foam::zoneToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding all cells of cell zones "
             << flatOutput(selectedZones_) << " ..." << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing all cells of cell zones "
             << flatOutput(selectedZones_) << " ..." << endl;
diff --git a/src/meshTools/sets/cellZoneSources/setToCellZone/setToCellZone.C b/src/meshTools/sets/cellZoneSources/setToCellZone/setToCellZone.C
index 0a6e6e8fe9e3e8457bf35d53b8e4862563919ab8..51c55942d2d817793040a4faaf1be2cb2c254084 100644
--- a/src/meshTools/sets/cellZoneSources/setToCellZone/setToCellZone.C
+++ b/src/meshTools/sets/cellZoneSources/setToCellZone/setToCellZone.C
@@ -96,9 +96,9 @@ void Foam::setToCellZone::applyToSet
     }
     else
     {
-        cellZoneSet& fzSet = refCast<cellZoneSet>(set);
+        cellZoneSet& zoneSet = refCast<cellZoneSet>(set);
 
-        if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+        if (action == topoSetSource::ADD || action == topoSetSource::NEW)
         {
             Info<< "    Adding all cells from cellSet " << setName_
                 << " ..." << endl;
@@ -107,20 +107,20 @@ void Foam::setToCellZone::applyToSet
             cellSet fSet(mesh_, setName_);
 
             // Start off from copy
-            DynamicList<label> newAddressing(fzSet.addressing());
+            DynamicList<label> newAddressing(zoneSet.addressing());
 
             for (const label celli : fSet)
             {
-                if (!fzSet.found(celli))
+                if (!zoneSet.found(celli))
                 {
                     newAddressing.append(celli);
                 }
             }
 
-            fzSet.addressing().transfer(newAddressing);
-            fzSet.updateSet();
+            zoneSet.addressing().transfer(newAddressing);
+            zoneSet.updateSet();
         }
-        else if (action == topoSetSource::DELETE)
+        else if (action == topoSetSource::SUBTRACT)
         {
             Info<< "    Removing all cells from cellSet " << setName_
                 << " ..." << endl;
@@ -129,17 +129,17 @@ void Foam::setToCellZone::applyToSet
             cellSet loadedSet(mesh_, setName_);
 
             // Start off empty
-            DynamicList<label> newAddressing(fzSet.addressing().size());
+            DynamicList<label> newAddressing(zoneSet.addressing().size());
 
-            forAll(fzSet.addressing(), i)
+            forAll(zoneSet.addressing(), i)
             {
-                if (!loadedSet.found(fzSet.addressing()[i]))
+                if (!loadedSet.found(zoneSet.addressing()[i]))
                 {
-                    newAddressing.append(fzSet.addressing()[i]);
+                    newAddressing.append(zoneSet.addressing()[i]);
                 }
             }
-            fzSet.addressing().transfer(newAddressing);
-            fzSet.updateSet();
+            zoneSet.addressing().transfer(newAddressing);
+            zoneSet.updateSet();
         }
     }
 }
diff --git a/src/meshTools/sets/faceSources/boundaryToFace/boundaryToFace.C b/src/meshTools/sets/faceSources/boundaryToFace/boundaryToFace.C
index 73d8336a89dfaae7f214b2b27a101fd4fbef6d81..c788a3aeee51283eebfb438192cf83f963067e74 100644
--- a/src/meshTools/sets/faceSources/boundaryToFace/boundaryToFace.C
+++ b/src/meshTools/sets/faceSources/boundaryToFace/boundaryToFace.C
@@ -113,13 +113,13 @@ void Foam::boundaryToFace::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding all boundary faces ..." << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing all boundary faces ..." << endl;
 
diff --git a/src/meshTools/sets/faceSources/boxToFace/boxToFace.C b/src/meshTools/sets/faceSources/boxToFace/boxToFace.C
index 572e1ffd7ce472c6f69a455b2ac9955cf13870af..1a8bbd1d122c3686bc11302526ba6d53425766c6 100644
--- a/src/meshTools/sets/faceSources/boxToFace/boxToFace.C
+++ b/src/meshTools/sets/faceSources/boxToFace/boxToFace.C
@@ -142,13 +142,13 @@ void Foam::boxToFace::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding faces with centre within boxes " << bbs_ << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing faces with centre within boxes " << bbs_ << endl;
 
diff --git a/src/meshTools/sets/faceSources/cellToFace/cellToFace.C b/src/meshTools/sets/faceSources/cellToFace/cellToFace.C
index 34dc77bfe827952c529e4a582cf757602b17e440..4147aece2ca44fbd981d19dcb3a1ef14b0549d14 100644
--- a/src/meshTools/sets/faceSources/cellToFace/cellToFace.C
+++ b/src/meshTools/sets/faceSources/cellToFace/cellToFace.C
@@ -196,14 +196,14 @@ void Foam::cellToFace::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding faces according to cellSet " << setName_
             << " ..." << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing faces according to cellSet " << setName_
             << " ..." << endl;
diff --git a/src/meshTools/sets/faceSources/cylinderAnnulusToFace/cylinderAnnulusToFace.C b/src/meshTools/sets/faceSources/cylinderAnnulusToFace/cylinderAnnulusToFace.C
index 8366a41f2f5fe415ac76b2be6b296b87a2239632..89db47312e323dd7c7f280d02995cbd6a853326f 100644
--- a/src/meshTools/sets/faceSources/cylinderAnnulusToFace/cylinderAnnulusToFace.C
+++ b/src/meshTools/sets/faceSources/cylinderAnnulusToFace/cylinderAnnulusToFace.C
@@ -158,7 +158,7 @@ void Foam::cylinderAnnulusToFace::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding faces with centre within cylinder annulus,"
             << " with p1 = "
@@ -168,7 +168,7 @@ void Foam::cylinderAnnulusToFace::applyToSet
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing faces with centre within cylinder annulus,"
             << " with p1 = "
diff --git a/src/meshTools/sets/faceSources/cylinderToFace/cylinderToFace.C b/src/meshTools/sets/faceSources/cylinderToFace/cylinderToFace.C
index 6e40dda85cf11ddd3631c3e2b5c26a64701868cd..ec993610b0588c09f5c75f38c0ecc7b01a128df5 100644
--- a/src/meshTools/sets/faceSources/cylinderToFace/cylinderToFace.C
+++ b/src/meshTools/sets/faceSources/cylinderToFace/cylinderToFace.C
@@ -142,7 +142,7 @@ void Foam::cylinderToFace::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding faces with centre within cylinder, with  p1 = "
             << point1_ << ", p2 = " << point2_ << ", radius = " << radius_
@@ -150,7 +150,7 @@ void Foam::cylinderToFace::applyToSet
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing faces with centre within cylinder, with p1 = "
             << point1_ << ", p2 = " << point2_ << ", radius = " << radius_
diff --git a/src/meshTools/sets/faceSources/faceToFace/faceToFace.C b/src/meshTools/sets/faceSources/faceToFace/faceToFace.C
index 4310fda9958f9fbf48f407afa5246f0e1172ab78..1bfa44e824d9a4c2805a0308004e2186219a845f 100644
--- a/src/meshTools/sets/faceSources/faceToFace/faceToFace.C
+++ b/src/meshTools/sets/faceSources/faceToFace/faceToFace.C
@@ -94,7 +94,7 @@ void Foam::faceToFace::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding all faces from faceSet " << setName_ << " ..."
             << endl;
@@ -104,7 +104,7 @@ void Foam::faceToFace::applyToSet
 
         set.addSet(loadedSet);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing all faces from faceSet " << setName_ << " ..."
             << endl;
@@ -112,7 +112,7 @@ void Foam::faceToFace::applyToSet
         // Load the set
         faceSet loadedSet(mesh_, setName_);
 
-        set.deleteSet(loadedSet);
+        set.subtractSet(loadedSet);
     }
 }
 
diff --git a/src/meshTools/sets/faceSources/labelToFace/labelToFace.C b/src/meshTools/sets/faceSources/labelToFace/labelToFace.C
index 0f085a42324212dafec6985c234313a8ed85e773..0a6147550b90d0398a3b53e4de6418281ace57c9 100644
--- a/src/meshTools/sets/faceSources/labelToFace/labelToFace.C
+++ b/src/meshTools/sets/faceSources/labelToFace/labelToFace.C
@@ -120,13 +120,13 @@ void Foam::labelToFace::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding faces mentioned in dictionary" << " ..." << endl;
 
         addOrDelete(set, labels_, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing faces mentioned dictionary" << " ..." << endl;
 
diff --git a/src/meshTools/sets/faceSources/normalToFace/normalToFace.C b/src/meshTools/sets/faceSources/normalToFace/normalToFace.C
index 3c5c309afcb9fd32d62faeb2fe41f074a6251d0d..2bf77f2971002af19c64244c82daa48da7cce9e3 100644
--- a/src/meshTools/sets/faceSources/normalToFace/normalToFace.C
+++ b/src/meshTools/sets/faceSources/normalToFace/normalToFace.C
@@ -128,7 +128,7 @@ void Foam::normalToFace::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding faces according to normal being aligned with "
             << normal_ << " (to within " << tol_ << ") ..." << endl;
@@ -139,11 +139,11 @@ void Foam::normalToFace::applyToSet
 
             if (mag(1 - (n & normal_)) < tol_)
             {
-                set.insert(facei);
+                set.set(facei);
             }
         }
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing faces according to normal being aligned with "
             << normal_ << " (to within " << tol_ << ") ..." << endl;
@@ -160,7 +160,7 @@ void Foam::normalToFace::applyToSet
             }
         }
 
-        set.erase(toBeRemoved);
+        set.unset(toBeRemoved);
     }
 }
 
diff --git a/src/meshTools/sets/faceSources/patchToFace/patchToFace.C b/src/meshTools/sets/faceSources/patchToFace/patchToFace.C
index 8a3045f1b7b7a8fbeb5118053e0b1bacf6fa075d..46da30cbe9ae811c2b39920e81f97ecf85dac308 100644
--- a/src/meshTools/sets/faceSources/patchToFace/patchToFace.C
+++ b/src/meshTools/sets/faceSources/patchToFace/patchToFace.C
@@ -152,14 +152,14 @@ void Foam::patchToFace::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding all faces of patches "
             << flatOutput(selectedPatches_) << " ..." << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing all faces of patches "
             << flatOutput(selectedPatches_) << " ..." << endl;
diff --git a/src/meshTools/sets/faceSources/pointToFace/pointToFace.C b/src/meshTools/sets/faceSources/pointToFace/pointToFace.C
index 7c0ca17972569ebd5aeaa565bfc37b135a45b7de..8b6d9168b911308a89c8d18a6f4327afb044b53a 100644
--- a/src/meshTools/sets/faceSources/pointToFace/pointToFace.C
+++ b/src/meshTools/sets/faceSources/pointToFace/pointToFace.C
@@ -204,14 +204,14 @@ void Foam::pointToFace::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding faces according to pointSet " << setName_
             << " ..." << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing faces according to pointSet " << setName_
             << " ..." << endl;
diff --git a/src/meshTools/sets/faceSources/regionToFace/regionToFace.C b/src/meshTools/sets/faceSources/regionToFace/regionToFace.C
index a06e5d53afa8b7bf7140a40892c92502b835eace..a5ebb929e785c04207bfa018c3328954ddb6e086 100644
--- a/src/meshTools/sets/faceSources/regionToFace/regionToFace.C
+++ b/src/meshTools/sets/faceSources/regionToFace/regionToFace.C
@@ -234,7 +234,7 @@ void Foam::regionToFace::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding all faces of connected region of set "
             << setName_
@@ -243,7 +243,7 @@ void Foam::regionToFace::applyToSet
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing all cells of connected region of set "
             << setName_
diff --git a/src/meshTools/sets/faceSources/zoneToFace/zoneToFace.C b/src/meshTools/sets/faceSources/zoneToFace/zoneToFace.C
index 1830bb94b2fc60a2fa6ec25777d18f8efd8bbf3a..becbcb66dc2c78caf56757b8f5ef9a44dab71537 100644
--- a/src/meshTools/sets/faceSources/zoneToFace/zoneToFace.C
+++ b/src/meshTools/sets/faceSources/zoneToFace/zoneToFace.C
@@ -152,14 +152,14 @@ void Foam::zoneToFace::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding all faces of face zones "
             << flatOutput(selectedZones_) << " ..." << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing all faces of face zones "
             << flatOutput(selectedZones_) << " ..." << endl;
diff --git a/src/meshTools/sets/faceZoneSources/faceZoneToFaceZone/faceZoneToFaceZone.C b/src/meshTools/sets/faceZoneSources/faceZoneToFaceZone/faceZoneToFaceZone.C
index dfd056ae0ad2034622a9aae9d4d2fb8ebec2e251..db90f92d511b384cbc34c3b52ffeabe5a80cc411 100644
--- a/src/meshTools/sets/faceZoneSources/faceZoneToFaceZone/faceZoneToFaceZone.C
+++ b/src/meshTools/sets/faceZoneSources/faceZoneToFaceZone/faceZoneToFaceZone.C
@@ -96,9 +96,9 @@ void Foam::faceZoneToFaceZone::applyToSet
     }
     else
     {
-        faceZoneSet& fSet = refCast<faceZoneSet>(set);
+        faceZoneSet& zoneSet = refCast<faceZoneSet>(set);
 
-        if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+        if (action == topoSetSource::ADD || action == topoSetSource::NEW)
         {
             Info<< "    Adding all faces from faceZone " << setName_ << " ..."
                 << endl;
@@ -106,22 +106,22 @@ void Foam::faceZoneToFaceZone::applyToSet
             // Load the set
             faceZoneSet loadedSet(mesh_, setName_);
 
-            DynamicList<label> newAddressing(fSet.addressing());
-            DynamicList<bool> newFlipMap(fSet.flipMap());
+            DynamicList<label> newAddressing(zoneSet.addressing());
+            DynamicList<bool> newFlipMap(zoneSet.flipMap());
 
             forAll(loadedSet.addressing(), i)
             {
-                if (!fSet.found(loadedSet.addressing()[i]))
+                if (!zoneSet.found(loadedSet.addressing()[i]))
                 {
                     newAddressing.append(loadedSet.addressing()[i]);
                     newFlipMap.append(loadedSet.flipMap()[i]);
                 }
             }
-            fSet.addressing().transfer(newAddressing);
-            fSet.flipMap().transfer(newFlipMap);
-            fSet.updateSet();
+            zoneSet.addressing().transfer(newAddressing);
+            zoneSet.flipMap().transfer(newFlipMap);
+            zoneSet.updateSet();
         }
-        else if (action == topoSetSource::DELETE)
+        else if (action == topoSetSource::SUBTRACT)
         {
             Info<< "    Removing all faces from faceZone " << setName_ << " ..."
                 << endl;
@@ -129,20 +129,20 @@ void Foam::faceZoneToFaceZone::applyToSet
             // Load the set
             faceZoneSet loadedSet(mesh_, setName_);
 
-            DynamicList<label> newAddressing(fSet.addressing().size());
-            DynamicList<bool> newFlipMap(fSet.flipMap().size());
+            DynamicList<label> newAddressing(zoneSet.addressing().size());
+            DynamicList<bool> newFlipMap(zoneSet.flipMap().size());
 
-            forAll(fSet.addressing(), i)
+            forAll(zoneSet.addressing(), i)
             {
-                if (!loadedSet.found(fSet.addressing()[i]))
+                if (!loadedSet.found(zoneSet.addressing()[i]))
                 {
-                    newAddressing.append(fSet.addressing()[i]);
-                    newFlipMap.append(fSet.flipMap()[i]);
+                    newAddressing.append(zoneSet.addressing()[i]);
+                    newFlipMap.append(zoneSet.flipMap()[i]);
                 }
             }
-            fSet.addressing().transfer(newAddressing);
-            fSet.flipMap().transfer(newFlipMap);
-            fSet.updateSet();
+            zoneSet.addressing().transfer(newAddressing);
+            zoneSet.flipMap().transfer(newFlipMap);
+            zoneSet.updateSet();
         }
     }
 }
diff --git a/src/meshTools/sets/faceZoneSources/searchableSurfaceToFaceZone/searchableSurfaceToFaceZone.C b/src/meshTools/sets/faceZoneSources/searchableSurfaceToFaceZone/searchableSurfaceToFaceZone.C
index 173c852cd691b8626b248536a89209be449ff3a6..90472163020a43d55fa08522a4ad1b2a9006a9c0 100644
--- a/src/meshTools/sets/faceZoneSources/searchableSurfaceToFaceZone/searchableSurfaceToFaceZone.C
+++ b/src/meshTools/sets/faceZoneSources/searchableSurfaceToFaceZone/searchableSurfaceToFaceZone.C
@@ -162,7 +162,7 @@ void Foam::searchableSurfaceToFaceZone::applyToSet
         // Select intersected faces
         // ~~~~~~~~~~~~~~~~~~~~~~~~
 
-        if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+        if (action == topoSetSource::ADD || action == topoSetSource::NEW)
         {
             Info<< "    Adding all faces from surface "
                 << surfacePtr_().name() << " ..." << endl;
@@ -184,7 +184,7 @@ void Foam::searchableSurfaceToFaceZone::applyToSet
             fzSet.flipMap().transfer(newFlipMap);
             fzSet.updateSet();
         }
-        else if (action == topoSetSource::DELETE)
+        else if (action == topoSetSource::SUBTRACT)
         {
             Info<< "    Removing all faces from surface "
                 << surfacePtr_().name() << " ..." << endl;
diff --git a/src/meshTools/sets/faceZoneSources/setAndNormalToFaceZone/setAndNormalToFaceZone.C b/src/meshTools/sets/faceZoneSources/setAndNormalToFaceZone/setAndNormalToFaceZone.C
index 3b4e6ed5b7a7978beca40adcbbcf66936279b8b8..bd34ad6cf9349e211c4719dfe5f8f72c7e34e70b 100644
--- a/src/meshTools/sets/faceZoneSources/setAndNormalToFaceZone/setAndNormalToFaceZone.C
+++ b/src/meshTools/sets/faceZoneSources/setAndNormalToFaceZone/setAndNormalToFaceZone.C
@@ -100,9 +100,9 @@ void Foam::setAndNormalToFaceZone::applyToSet
     }
     else
     {
-        faceZoneSet& fzSet = refCast<faceZoneSet>(set);
+        faceZoneSet& zoneSet = refCast<faceZoneSet>(set);
 
-        if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+        if (action == topoSetSource::ADD || action == topoSetSource::NEW)
         {
             Info<< "    Adding all faces from faceSet " << setName_
                 << " ..." << endl;
@@ -112,15 +112,15 @@ void Foam::setAndNormalToFaceZone::applyToSet
             labelHashSet& faceIds = loadedSet;
 
             // Start off from copy
-            DynamicList<label> newAddressing(fzSet.addressing());
-            DynamicList<bool> newFlipMap(fzSet.flipMap());
+            DynamicList<label> newAddressing(zoneSet.addressing());
+            DynamicList<bool> newFlipMap(zoneSet.flipMap());
 
             const faceList& faces = mesh_.faces();
             const pointField& points = mesh_.points();
 
             for (const label facei : faceIds)
             {
-                if (!fzSet.found(facei))
+                if (!zoneSet.found(facei))
                 {
                     newAddressing.append(facei);
 
@@ -136,11 +136,11 @@ void Foam::setAndNormalToFaceZone::applyToSet
                 }
             }
 
-            fzSet.addressing().transfer(newAddressing);
-            fzSet.flipMap().transfer(newFlipMap);
-            fzSet.updateSet();
+            zoneSet.addressing().transfer(newAddressing);
+            zoneSet.flipMap().transfer(newFlipMap);
+            zoneSet.updateSet();
         }
-        else if (action == topoSetSource::DELETE)
+        else if (action == topoSetSource::SUBTRACT)
         {
             Info<< "    Removing all faces from faceSet " << setName_
                 << " ..." << endl;
@@ -149,20 +149,20 @@ void Foam::setAndNormalToFaceZone::applyToSet
             faceSet loadedSet(mesh_, setName_);
 
             // Start off empty
-            DynamicList<label> newAddressing(fzSet.addressing().size());
-            DynamicList<bool> newFlipMap(fzSet.flipMap().size());
+            DynamicList<label> newAddressing(zoneSet.addressing().size());
+            DynamicList<bool> newFlipMap(zoneSet.flipMap().size());
 
-            forAll(fzSet.addressing(), i)
+            forAll(zoneSet.addressing(), i)
             {
-                if (!loadedSet.found(fzSet.addressing()[i]))
+                if (!loadedSet.found(zoneSet.addressing()[i]))
                 {
-                    newAddressing.append(fzSet.addressing()[i]);
-                    newFlipMap.append(fzSet.flipMap()[i]);
+                    newAddressing.append(zoneSet.addressing()[i]);
+                    newFlipMap.append(zoneSet.flipMap()[i]);
                 }
             }
-            fzSet.addressing().transfer(newAddressing);
-            fzSet.flipMap().transfer(newFlipMap);
-            fzSet.updateSet();
+            zoneSet.addressing().transfer(newAddressing);
+            zoneSet.flipMap().transfer(newFlipMap);
+            zoneSet.updateSet();
         }
     }
 }
diff --git a/src/meshTools/sets/faceZoneSources/setToFaceZone/setToFaceZone.C b/src/meshTools/sets/faceZoneSources/setToFaceZone/setToFaceZone.C
index 3ed303102b5b2c44c094ca406cac2cea7b87bbde..411512705af331f916177815934a4b55478b1cda 100644
--- a/src/meshTools/sets/faceZoneSources/setToFaceZone/setToFaceZone.C
+++ b/src/meshTools/sets/faceZoneSources/setToFaceZone/setToFaceZone.C
@@ -97,9 +97,9 @@ void Foam::setToFaceZone::applyToSet
     }
     else
     {
-        faceZoneSet& fzSet = refCast<faceZoneSet>(set);
+        faceZoneSet& zoneSet = refCast<faceZoneSet>(set);
 
-        if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+        if (action == topoSetSource::ADD || action == topoSetSource::NEW)
         {
             Info<< "    Adding all faces from faceSet " << setName_
                 << " ..." << endl;
@@ -109,23 +109,23 @@ void Foam::setToFaceZone::applyToSet
             const labelHashSet& faceLabels = loadedSet;
 
             // Start off from copy
-            DynamicList<label> newAddressing(fzSet.addressing());
-            DynamicList<bool> newFlipMap(fzSet.flipMap());
+            DynamicList<label> newAddressing(zoneSet.addressing());
+            DynamicList<bool> newFlipMap(zoneSet.flipMap());
 
             for (const label facei : faceLabels)
             {
-                if (!fzSet.found(facei))
+                if (!zoneSet.found(facei))
                 {
                     newAddressing.append(facei);
                     newFlipMap.append(false);
                 }
             }
 
-            fzSet.addressing().transfer(newAddressing);
-            fzSet.flipMap().transfer(newFlipMap);
-            fzSet.updateSet();
+            zoneSet.addressing().transfer(newAddressing);
+            zoneSet.flipMap().transfer(newFlipMap);
+            zoneSet.updateSet();
         }
-        else if (action == topoSetSource::DELETE)
+        else if (action == topoSetSource::SUBTRACT)
         {
             Info<< "    Removing all faces from faceSet " << setName_
                 << " ..." << endl;
@@ -134,20 +134,20 @@ void Foam::setToFaceZone::applyToSet
             faceSet loadedSet(mesh_, setName_);
 
             // Start off empty
-            DynamicList<label> newAddressing(fzSet.addressing().size());
-            DynamicList<bool> newFlipMap(fzSet.flipMap().size());
+            DynamicList<label> newAddressing(zoneSet.addressing().size());
+            DynamicList<bool> newFlipMap(zoneSet.flipMap().size());
 
-            forAll(fzSet.addressing(), i)
+            forAll(zoneSet.addressing(), i)
             {
-                if (!loadedSet.found(fzSet.addressing()[i]))
+                if (!loadedSet.found(zoneSet.addressing()[i]))
                 {
-                    newAddressing.append(fzSet.addressing()[i]);
-                    newFlipMap.append(fzSet.flipMap()[i]);
+                    newAddressing.append(zoneSet.addressing()[i]);
+                    newFlipMap.append(zoneSet.flipMap()[i]);
                 }
             }
-            fzSet.addressing().transfer(newAddressing);
-            fzSet.flipMap().transfer(newFlipMap);
-            fzSet.updateSet();
+            zoneSet.addressing().transfer(newAddressing);
+            zoneSet.flipMap().transfer(newFlipMap);
+            zoneSet.updateSet();
         }
     }
 }
diff --git a/src/meshTools/sets/faceZoneSources/setsToFaceZone/setsToFaceZone.C b/src/meshTools/sets/faceZoneSources/setsToFaceZone/setsToFaceZone.C
index 8c016ea7f6cf998c601cf2d321d71f6f18187f2e..776f0b06c97b9b4e161f35cd763b266805180582 100644
--- a/src/meshTools/sets/faceZoneSources/setsToFaceZone/setsToFaceZone.C
+++ b/src/meshTools/sets/faceZoneSources/setsToFaceZone/setsToFaceZone.C
@@ -106,9 +106,9 @@ void Foam::setsToFaceZone::applyToSet
     }
     else
     {
-        faceZoneSet& fzSet = refCast<faceZoneSet>(set);
+        faceZoneSet& zoneSet = refCast<faceZoneSet>(set);
 
-        if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+        if (action == topoSetSource::ADD || action == topoSetSource::NEW)
         {
             Info<< "    Adding all faces from faceSet " << faceSetName_
                 << " ..." << endl;
@@ -118,14 +118,14 @@ void Foam::setsToFaceZone::applyToSet
             cellSet cSet(mesh_, cellSetName_);
 
             // Start off from copy
-            DynamicList<label> newAddressing(fzSet.addressing());
-            DynamicList<bool> newFlipMap(fzSet.flipMap());
+            DynamicList<label> newAddressing(zoneSet.addressing());
+            DynamicList<bool> newFlipMap(zoneSet.flipMap());
 
             forAllConstIter(faceSet, fSet, iter)
             {
                 label facei = iter.key();
 
-                if (!fzSet.found(facei))
+                if (!zoneSet.found(facei))
                 {
                     bool flipFace = false;
 
@@ -176,11 +176,11 @@ void Foam::setsToFaceZone::applyToSet
                 }
             }
 
-            fzSet.addressing().transfer(newAddressing);
-            fzSet.flipMap().transfer(newFlipMap);
-            fzSet.updateSet();
+            zoneSet.addressing().transfer(newAddressing);
+            zoneSet.flipMap().transfer(newFlipMap);
+            zoneSet.updateSet();
         }
-        else if (action == topoSetSource::DELETE)
+        else if (action == topoSetSource::SUBTRACT)
         {
             Info<< "    Removing all faces from faceSet " << faceSetName_
                 << " ..." << endl;
@@ -189,20 +189,20 @@ void Foam::setsToFaceZone::applyToSet
             faceZoneSet loadedSet(mesh_, faceSetName_);
 
             // Start off empty
-            DynamicList<label> newAddressing(fzSet.addressing().size());
-            DynamicList<bool> newFlipMap(fzSet.flipMap().size());
+            DynamicList<label> newAddressing(zoneSet.addressing().size());
+            DynamicList<bool> newFlipMap(zoneSet.flipMap().size());
 
-            forAll(fzSet.addressing(), i)
+            forAll(zoneSet.addressing(), i)
             {
-                if (!loadedSet.found(fzSet.addressing()[i]))
+                if (!loadedSet.found(zoneSet.addressing()[i]))
                 {
-                    newAddressing.append(fzSet.addressing()[i]);
-                    newFlipMap.append(fzSet.flipMap()[i]);
+                    newAddressing.append(zoneSet.addressing()[i]);
+                    newFlipMap.append(zoneSet.flipMap()[i]);
                 }
             }
-            fzSet.addressing().transfer(newAddressing);
-            fzSet.flipMap().transfer(newFlipMap);
-            fzSet.updateSet();
+            zoneSet.addressing().transfer(newAddressing);
+            zoneSet.flipMap().transfer(newFlipMap);
+            zoneSet.updateSet();
         }
     }
 }
diff --git a/src/meshTools/sets/pointSources/boxToPoint/boxToPoint.C b/src/meshTools/sets/pointSources/boxToPoint/boxToPoint.C
index cec79cccb2fc67252d77b5e0656a802ef6450678..add0cf7f4c0e861266a8ef6310fc1233450741b0 100644
--- a/src/meshTools/sets/pointSources/boxToPoint/boxToPoint.C
+++ b/src/meshTools/sets/pointSources/boxToPoint/boxToPoint.C
@@ -142,14 +142,14 @@ void Foam::boxToPoint::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding points that are within boxes " << bbs_ << " ..."
             << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing points that are within boxes " << bbs_ << " ..."
             << endl;
diff --git a/src/meshTools/sets/pointSources/cellToPoint/cellToPoint.C b/src/meshTools/sets/pointSources/cellToPoint/cellToPoint.C
index 6b21b8415b762c92f96eefd18457c668e03cf464..c18b5d37d2fdac786001d647b9af60af7dc72e81 100644
--- a/src/meshTools/sets/pointSources/cellToPoint/cellToPoint.C
+++ b/src/meshTools/sets/pointSources/cellToPoint/cellToPoint.C
@@ -133,13 +133,13 @@ void Foam::cellToPoint::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding from " << setName_ << " ..." << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing from " << setName_ << " ..." << endl;
 
diff --git a/src/meshTools/sets/pointSources/faceToPoint/faceToPoint.C b/src/meshTools/sets/pointSources/faceToPoint/faceToPoint.C
index 8b0439bed6fe8904e4b4673cfc77ec998d85aaea..f2d50b750a71583ba7b794d705dad4c1921f10d9 100644
--- a/src/meshTools/sets/pointSources/faceToPoint/faceToPoint.C
+++ b/src/meshTools/sets/pointSources/faceToPoint/faceToPoint.C
@@ -127,14 +127,14 @@ void Foam::faceToPoint::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding points from face in faceSet " << setName_
             << " ..." << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing points from face in faceSet " << setName_
             << " ..." << endl;
diff --git a/src/meshTools/sets/pointSources/labelToPoint/labelToPoint.C b/src/meshTools/sets/pointSources/labelToPoint/labelToPoint.C
index f6c2ce4577755650ee9ecc0202833997f5267969..0e6455d7f6393c56c9d0ec9881dc5c45dc16a661 100644
--- a/src/meshTools/sets/pointSources/labelToPoint/labelToPoint.C
+++ b/src/meshTools/sets/pointSources/labelToPoint/labelToPoint.C
@@ -116,13 +116,13 @@ void Foam::labelToPoint::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding points mentioned in dictionary" << " ..." << endl;
 
         addOrDelete(set, labels_, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing points mentioned in dictionary" << " ..." << endl;
 
diff --git a/src/meshTools/sets/pointSources/nearestToPoint/nearestToPoint.C b/src/meshTools/sets/pointSources/nearestToPoint/nearestToPoint.C
index a7c62b94740d0520c7611f76df46a05fc71953b4..240509ca457102f53342d38ea7a9c37898162b3a 100644
--- a/src/meshTools/sets/pointSources/nearestToPoint/nearestToPoint.C
+++ b/src/meshTools/sets/pointSources/nearestToPoint/nearestToPoint.C
@@ -167,13 +167,13 @@ void Foam::nearestToPoint::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding points nearest to " << points_ << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing points nearest to " << points_ << endl;
 
diff --git a/src/meshTools/sets/pointSources/pointToPoint/pointToPoint.C b/src/meshTools/sets/pointSources/pointToPoint/pointToPoint.C
index 120f50c12988c3982cb18720ced9968028e86678..ebab5698dcfd489179045bd0c4d66e7ad0e1316a 100644
--- a/src/meshTools/sets/pointSources/pointToPoint/pointToPoint.C
+++ b/src/meshTools/sets/pointSources/pointToPoint/pointToPoint.C
@@ -90,7 +90,7 @@ void Foam::pointToPoint::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding all from pointSet " << setName_ << " ..." << endl;
 
@@ -99,14 +99,14 @@ void Foam::pointToPoint::applyToSet
 
         set.addSet(loadedSet);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing all from pointSet " << setName_ << " ..." << endl;
 
         // Load the set
         pointSet loadedSet(mesh_, setName_);
 
-        set.deleteSet(loadedSet);
+        set.subtractSet(loadedSet);
     }
 }
 
diff --git a/src/meshTools/sets/pointSources/surfaceToPoint/surfaceToPoint.C b/src/meshTools/sets/pointSources/surfaceToPoint/surfaceToPoint.C
index 729426e5b801db26305b3fcbf893e2fef324d01d..d44b69e3a1029b1e5557e8275742f487e533de97 100644
--- a/src/meshTools/sets/pointSources/surfaceToPoint/surfaceToPoint.C
+++ b/src/meshTools/sets/pointSources/surfaceToPoint/surfaceToPoint.C
@@ -188,14 +188,14 @@ void Foam::surfaceToPoint::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding points in relation to surface " << surfName_
             << " ..." << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing points in relation to surface " << surfName_
             << " ..." << endl;
diff --git a/src/meshTools/sets/pointSources/zoneToPoint/zoneToPoint.C b/src/meshTools/sets/pointSources/zoneToPoint/zoneToPoint.C
index 3879a24b178715eea73b9013d440a1a719b0fe6f..3781ff5ccb939aa8977afea9056a207178f9c761 100644
--- a/src/meshTools/sets/pointSources/zoneToPoint/zoneToPoint.C
+++ b/src/meshTools/sets/pointSources/zoneToPoint/zoneToPoint.C
@@ -152,14 +152,14 @@ void Foam::zoneToPoint::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding all points of point zones "
             << flatOutput(selectedZones_) << " ..." << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing all points of point zones "
             << flatOutput(selectedZones_) << " ..." << endl;
diff --git a/src/meshTools/sets/pointZoneSources/setToPointZone/setToPointZone.C b/src/meshTools/sets/pointZoneSources/setToPointZone/setToPointZone.C
index fd714d51fa247fe61e1d5dd9d27d6c4b6f9d52d5..c9b58da462dd4dea66f98b8c9ff8f74d4896854f 100644
--- a/src/meshTools/sets/pointZoneSources/setToPointZone/setToPointZone.C
+++ b/src/meshTools/sets/pointZoneSources/setToPointZone/setToPointZone.C
@@ -96,9 +96,9 @@ void Foam::setToPointZone::applyToSet
     }
     else
     {
-        pointZoneSet& fzSet = refCast<pointZoneSet>(set);
+        pointZoneSet& zoneSet = refCast<pointZoneSet>(set);
 
-        if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+        if (action == topoSetSource::ADD || action == topoSetSource::NEW)
         {
             Info<< "    Adding all points from pointSet " << setName_
                 << " ..." << endl;
@@ -108,20 +108,20 @@ void Foam::setToPointZone::applyToSet
             const labelHashSet& pointLabels = loadedSet;
 
             // Start off from copy
-            DynamicList<label> newAddressing(fzSet.addressing());
+            DynamicList<label> newAddressing(zoneSet.addressing());
 
             for (const label pointi : pointLabels)
             {
-                if (!fzSet.found(pointi))
+                if (!zoneSet.found(pointi))
                 {
                     newAddressing.append(pointi);
                 }
             }
 
-            fzSet.addressing().transfer(newAddressing);
-            fzSet.updateSet();
+            zoneSet.addressing().transfer(newAddressing);
+            zoneSet.updateSet();
         }
-        else if (action == topoSetSource::DELETE)
+        else if (action == topoSetSource::SUBTRACT)
         {
             Info<< "    Removing all points from pointSet " << setName_
                 << " ..." << endl;
@@ -130,17 +130,17 @@ void Foam::setToPointZone::applyToSet
             pointSet loadedSet(mesh_, setName_);
 
             // Start off empty
-            DynamicList<label> newAddressing(fzSet.addressing().size());
+            DynamicList<label> newAddressing(zoneSet.addressing().size());
 
-            forAll(fzSet.addressing(), i)
+            forAll(zoneSet.addressing(), i)
             {
-                if (!loadedSet.found(fzSet.addressing()[i]))
+                if (!loadedSet.found(zoneSet.addressing()[i]))
                 {
-                    newAddressing.append(fzSet.addressing()[i]);
+                    newAddressing.append(zoneSet.addressing()[i]);
                 }
             }
-            fzSet.addressing().transfer(newAddressing);
-            fzSet.updateSet();
+            zoneSet.addressing().transfer(newAddressing);
+            zoneSet.updateSet();
         }
     }
 }
diff --git a/src/meshTools/sets/topoSetSource/topoSetSource.C b/src/meshTools/sets/topoSetSource/topoSetSource.C
index fa95d9d27b8407d06c3355ef281514ee6d125d7e..e31efe15c4ddfcdfdc5d240ed1ea6f71b33f1936 100644
--- a/src/meshTools/sets/topoSetSource/topoSetSource.C
+++ b/src/meshTools/sets/topoSetSource/topoSetSource.C
@@ -3,7 +3,7 @@
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
     \\  /    A nd           | Copyright (C) 2011-2016 OpenFOAM Foundation
-     \\/     M anipulation  |
+     \\/     M anipulation  | Copyright (C) 2018 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -46,14 +46,15 @@ const Foam::Enum
 >
 Foam::topoSetSource::actionNames
 ({
-    { setAction::CLEAR, "clear" },
-    { setAction::NEW, "new" },
-    { setAction::INVERT, "invert" },
     { setAction::ADD, "add" },
-    { setAction::DELETE, "delete" },
+    { setAction::SUBTRACT, "subtract" },
     { setAction::SUBSET, "subset" },
-    { setAction::LIST, "list" },
+    { setAction::INVERT, "invert" },
+    { setAction::CLEAR, "clear" },
+    { setAction::NEW, "new" },
     { setAction::REMOVE, "remove" },
+    { setAction::LIST, "list" },
+    { setAction::SUBTRACT, "delete" },   // Compat (1806)
 });
 
 
@@ -169,11 +170,11 @@ void Foam::topoSetSource::addOrDelete
 {
     if (add)
     {
-        set.insert(id);
+        set.set(id);
     }
     else
     {
-        set.erase(id);
+        set.unset(id);
     }
 }
 
@@ -187,11 +188,11 @@ void Foam::topoSetSource::addOrDelete
 {
     if (add)
     {
-        set.insert(labels);
+        set.set(labels);
     }
     else
     {
-        set.erase(labels);
+        set.unset(labels);
     }
 }
 
diff --git a/src/meshTools/sets/topoSetSource/topoSetSource.H b/src/meshTools/sets/topoSetSource/topoSetSource.H
index 5a085b5b4b916ae9d97016bd714a161860d3f741..67511f048e71a0de7fdea573eccd9b35f3715058 100644
--- a/src/meshTools/sets/topoSetSource/topoSetSource.H
+++ b/src/meshTools/sets/topoSetSource/topoSetSource.H
@@ -69,26 +69,27 @@ public:
         //- Enumeration defining the types of sources
         enum sourceType
         {
-            CELLSETSOURCE,
-            FACESETSOURCE,
-            POINTSETSOURCE,
+            CELLSETSOURCE = 0x1,        //!< Cells
+            FACESETSOURCE = 0x2,        //!< Faces
+            POINTSETSOURCE = 0x4,       //!< Points
 
-            CELLZONESOURCE,
-            FACEZONESOURCE,
-            POINTZONESOURCE
+            CELLZONESOURCE = 0x11,      //!< Cells as zone
+            FACEZONESOURCE = 0x12,      //!< Faces as zone
+            POINTZONESOURCE = 0x14,     //!< Points as zone
         };
 
         //- Enumeration defining the valid actions
         enum setAction
         {
-            CLEAR,
-            NEW,
-            INVERT,
-            ADD,
-            DELETE,
-            SUBSET,
-            LIST,
-            REMOVE
+            ADD,                //!< Adds elements to the set
+            SUBTRACT,           //!< Removes elements from the set
+            SUBSET,             //!< Subset with elements in the set
+            INVERT,             //!< Invert the elements in the set
+            CLEAR,              //!< Clear the set, possibly creating it
+            NEW,                //!< Create a new set and ADD elemets to it
+            REMOVE,             //!< Remove the set (from the file system)
+            LIST,               //!< Print contents of the set
+            DELETE = SUBTRACT,  //!< \deprecated alias for SUBTRACT (OCT-2018)
         };
 
         //- The setActions text representations
diff --git a/src/meshTools/sets/topoSets/cellZoneSet.C b/src/meshTools/sets/topoSets/cellZoneSet.C
index 4168af394a85392f475992183eb3458656b153cd..0ca2fdc96da9e7187c27682c1d944088efa645b7 100644
--- a/src/meshTools/sets/topoSets/cellZoneSet.C
+++ b/src/meshTools/sets/topoSets/cellZoneSet.C
@@ -49,7 +49,7 @@ void Foam::cellZoneSet::updateSet()
 
     cellSet::clearStorage();
     cellSet::resize(2*addressing_.size());
-    cellSet::insert(addressing_);
+    cellSet::set(addressing_);
 }
 
 
@@ -189,7 +189,7 @@ void Foam::cellZoneSet::addSet(const topoSet& set)
 }
 
 
-void Foam::cellZoneSet::deleteSet(const topoSet& set)
+void Foam::cellZoneSet::subtractSet(const topoSet& set)
 {
     DynamicList<label> newAddressing(addressing_.size());
 
diff --git a/src/meshTools/sets/topoSets/cellZoneSet.H b/src/meshTools/sets/topoSets/cellZoneSet.H
index 8e21178a5e9cb1ba829c14d6f28b98f54f5da47f..c7e96c3058fb710b5e74dde45261ed04bab5ef94 100644
--- a/src/meshTools/sets/topoSets/cellZoneSet.H
+++ b/src/meshTools/sets/topoSets/cellZoneSet.H
@@ -122,8 +122,8 @@ public:
         //- Add elements present in set.
         virtual void addSet(const topoSet& set);
 
-        //- Delete elements present in set.
-        virtual void deleteSet(const topoSet& set);
+        //- Subtract elements present in set.
+        virtual void subtractSet(const topoSet& set);
 
         //- Sync cellSet across coupled patches; update cellZone from cellSet
         virtual void sync(const polyMesh& mesh);
diff --git a/src/meshTools/sets/topoSets/faceSet.C b/src/meshTools/sets/topoSets/faceSet.C
index 2de0053c38ebfae4447587d056747cf2b9d1a7ae..b4839065a8e9833a082f403f8fb06d9fac595918 100644
--- a/src/meshTools/sets/topoSets/faceSet.C
+++ b/src/meshTools/sets/topoSets/faceSet.C
@@ -143,7 +143,7 @@ void Foam::faceSet::sync(const polyMesh& mesh)
     {
         if (set[facei])
         {
-            if (insert(facei))
+            if (this->set(facei))
             {
                 ++nAdded;
             }
@@ -207,7 +207,7 @@ void Foam::faceSet::distribute(const mapDistributePolyMesh& map)
     {
         if (inSet[facei])
         {
-            insert(facei);
+            this->set(facei);
         }
     }
 }
diff --git a/src/meshTools/sets/topoSets/faceZoneSet.C b/src/meshTools/sets/topoSets/faceZoneSet.C
index 674beddc35d5cccbb431615e06fcb3be1e2d8a3a..ff0431ac69f1848b78e965e54fb105fec8f96d78 100644
--- a/src/meshTools/sets/topoSets/faceZoneSet.C
+++ b/src/meshTools/sets/topoSets/faceZoneSet.C
@@ -54,7 +54,7 @@ void Foam::faceZoneSet::updateSet()
 
     faceSet::clearStorage();
     faceSet::resize(2*addressing_.size());
-    faceSet::insert(addressing_);
+    faceSet::set(addressing_);
 }
 
 
@@ -260,7 +260,7 @@ void Foam::faceZoneSet::addSet(const topoSet& set)
 }
 
 
-void Foam::faceZoneSet::deleteSet(const topoSet& set)
+void Foam::faceZoneSet::subtractSet(const topoSet& set)
 {
     label nConflict = 0;
 
@@ -301,7 +301,7 @@ void Foam::faceZoneSet::deleteSet(const topoSet& set)
     if (nConflict > 0)
     {
         WarningInFunction
-            << "deleteSet : there are " << nConflict
+            << "subtractSet : there are " << nConflict
             << " faces with different orientation in faceZonesSets "
             << name() << " and " << set.name() << endl;
     }
diff --git a/src/meshTools/sets/topoSets/faceZoneSet.H b/src/meshTools/sets/topoSets/faceZoneSet.H
index c8c0014906705df414fc326c3b377aadfa797ae8..09d60624626c7c34d55b8f8ecde5015dc0658831 100644
--- a/src/meshTools/sets/topoSets/faceZoneSet.H
+++ b/src/meshTools/sets/topoSets/faceZoneSet.H
@@ -137,8 +137,8 @@ public:
         //- Add elements present in set.
         virtual void addSet(const topoSet& set);
 
-        //- Delete elements present in set.
-        virtual void deleteSet(const topoSet& set);
+        //- Subtract elements present in set.
+        virtual void subtractSet(const topoSet& set);
 
         //- Sync faceZoneSet across coupled patches.
         virtual void sync(const polyMesh& mesh);
diff --git a/src/meshTools/sets/topoSets/pointSet.C b/src/meshTools/sets/topoSets/pointSet.C
index ed4347a59d845decc6d7ec780879d102bd0e37da..d0c9459420de81c8a1b43d518bf8b32b51508102 100644
--- a/src/meshTools/sets/topoSets/pointSet.C
+++ b/src/meshTools/sets/topoSets/pointSet.C
@@ -153,7 +153,7 @@ void Foam::pointSet::sync(const polyMesh& mesh)
     {
         if (contents[pointi])
         {
-            newContents.insert(pointi);
+            newContents.set(pointi);
         }
     }
 
@@ -202,7 +202,7 @@ void Foam::pointSet::distribute(const mapDistributePolyMesh& map)
     {
         if (inSet[pointi])
         {
-            insert(pointi);
+            this->set(pointi);
         }
     }
 }
diff --git a/src/meshTools/sets/topoSets/pointZoneSet.C b/src/meshTools/sets/topoSets/pointZoneSet.C
index 06b8eba119f18f2a00a398c1568a56cd20fd7f7d..647adac1999070202ae9e081c96927187ff0a885 100644
--- a/src/meshTools/sets/topoSets/pointZoneSet.C
+++ b/src/meshTools/sets/topoSets/pointZoneSet.C
@@ -50,7 +50,7 @@ void Foam::pointZoneSet::updateSet()
 
     pointSet::clearStorage();
     pointSet::resize(2*addressing_.size());
-    pointSet::insert(addressing_);
+    pointSet::set(addressing_);
 }
 
 
@@ -189,7 +189,7 @@ void Foam::pointZoneSet::addSet(const topoSet& set)
 }
 
 
-void Foam::pointZoneSet::deleteSet(const topoSet& set)
+void Foam::pointZoneSet::subtractSet(const topoSet& set)
 {
     DynamicList<label> newAddressing(addressing_.size());
 
diff --git a/src/meshTools/sets/topoSets/pointZoneSet.H b/src/meshTools/sets/topoSets/pointZoneSet.H
index f32db072d9cff80930a8f6446e0e206ee110bcaa..a5668e2ed575b1805e82b030c496e881fc45f557 100644
--- a/src/meshTools/sets/topoSets/pointZoneSet.H
+++ b/src/meshTools/sets/topoSets/pointZoneSet.H
@@ -123,8 +123,8 @@ public:
         //- Add elements present in set.
         virtual void addSet(const topoSet& set);
 
-        //- Delete elements present in set.
-        virtual void deleteSet(const topoSet& set);
+        //- Subtract elements present in set.
+        virtual void subtractSet(const topoSet& set);
 
         //- Sync pointZoneSet across coupled patches.
         virtual void sync(const polyMesh& mesh);
diff --git a/src/meshTools/sets/topoSets/topoSet.C b/src/meshTools/sets/topoSets/topoSet.C
index c69ffa92ebba10322a1170f6339469e1cf3f7cc2..3b92d5c2a3462c6fdd2d9dee06a657a225af2527 100644
--- a/src/meshTools/sets/topoSets/topoSet.C
+++ b/src/meshTools/sets/topoSets/topoSet.C
@@ -174,7 +174,7 @@ void Foam::topoSet::updateLabels(const labelList& map)
 
             if (newId >= 0)
             {
-                newSet.insert(newId);
+                newSet.set(newId);
             }
         }
 
@@ -506,7 +506,7 @@ void Foam::topoSet::invert(const label maxLen)
     {
         if (!original.found(id))
         {
-            insert(id);
+            this->set(id);
         }
     }
 }
@@ -514,25 +514,31 @@ void Foam::topoSet::invert(const label maxLen)
 
 void Foam::topoSet::subset(const topoSet& set)
 {
-    // Only retain entries found in both HashSets
+    // Only retain entries found in both sets
     static_cast<labelHashSet&>(*this) &= set;
 }
 
 
 void Foam::topoSet::addSet(const topoSet& set)
 {
-    // Add entries to the HashSet
-    static_cast<labelHashSet&>(*this) += set;
+    // Add entries to the set
+    static_cast<labelHashSet&>(*this) |= set;
 }
 
 
-void Foam::topoSet::deleteSet(const topoSet& set)
+void Foam::topoSet::subtractSet(const topoSet& set)
 {
-    // Remove entries from the HashSet
+    // Subtract entries from the set
     static_cast<labelHashSet&>(*this) -= set;
 }
 
 
+void Foam::topoSet::deleteSet(const topoSet& set)
+{
+    this->subtractSet(set);
+}
+
+
 void Foam::topoSet::sync(const polyMesh&)
 {
     NotImplemented;
diff --git a/src/meshTools/sets/topoSets/topoSet.H b/src/meshTools/sets/topoSets/topoSet.H
index 7255caecbba7fa81027586c74780b9c30c56944b..5d5794dac5cdfd96d31c725b13d894edd98ead58 100644
--- a/src/meshTools/sets/topoSets/topoSet.H
+++ b/src/meshTools/sets/topoSets/topoSet.H
@@ -324,7 +324,11 @@ public:
         //- Add elements present in set.
         virtual void addSet(const topoSet& set);
 
-        //- Delete elements present in set.
+        //- Subtract elements present in set.
+        virtual void subtractSet(const topoSet& set);
+
+        //- Subtract elements present in set.
+        //  \deprecated use subtractSet instead (OCT-2018)
         virtual void deleteSet(const topoSet& set);
 
         //- Sync set across coupled patches.
diff --git a/src/meshTools/surfaceSets/surfaceSets.C b/src/meshTools/surfaceSets/surfaceSets.C
index 9309e963ece4571111f2a31d714436a732383b52..6b639055917c53ba4d25af305d0873baf508afb4 100644
--- a/src/meshTools/surfaceSets/surfaceSets.C
+++ b/src/meshTools/surfaceSets/surfaceSets.C
@@ -496,7 +496,7 @@ Foam::labelHashSet Foam::surfaceSets::getHangingCells
 //
 //    cellToCell deleteInsideSource(mesh, rawInside.name());
 //
-//    deleteInsideSource.applyToSet(topoSetSource::DELETE, cutCells);
+//    deleteInsideSource.applyToSet(topoSetSource::SUBTRACT, cutCells);
 //    Pout<< "Writing cut cells (" << cutCells.size() << ") to cellSet "
 //        << cutCells.instance()/cutCells.local()/cutCells.name()
 //        << endl << endl;
@@ -544,8 +544,8 @@ Foam::labelHashSet Foam::surfaceSets::getHangingCells
 //    cellSet inside(mesh, "inside", rawInside);
 //    cellSet outside(mesh, "outside", rawOutside);
 //
-//    pToCell.applyToSet(topoSetSource::DELETE, inside);
-//    pToCell.applyToSet(topoSetSource::DELETE, outside);
+//    pToCell.applyToSet(topoSetSource::SUBTRACT, inside);
+//    pToCell.applyToSet(topoSetSource::SUBTRACT, outside);
 //
 //    Pout<< nl
 //        << "Removed " << rawInside.size() - inside.size()
diff --git a/src/overset/regionsToCell/regionsToCell.C b/src/overset/regionsToCell/regionsToCell.C
index 99fea0c97c69b087bfa4c215fffb9d0aa66f06b5..500140f00ae60b1efc4e080742afa5ff814110de 100644
--- a/src/overset/regionsToCell/regionsToCell.C
+++ b/src/overset/regionsToCell/regionsToCell.C
@@ -463,14 +463,14 @@ void Foam::regionsToCell::applyToSet
     topoSet& set
 ) const
 {
-    if ((action == topoSetSource::NEW) || (action == topoSetSource::ADD))
+    if (action == topoSetSource::ADD || action == topoSetSource::NEW)
     {
         Info<< "    Adding all cells of connected region containing points "
             << insidePoints_ << " ..." << endl;
 
         combine(set, true);
     }
-    else if (action == topoSetSource::DELETE)
+    else if (action == topoSetSource::SUBTRACT)
     {
         Info<< "    Removing all cells of connected region containing points "
             << insidePoints_ << " ..." << endl;
diff --git a/tutorials/combustion/fireFoam/LES/compartmentFire/system/topoSetDict b/tutorials/combustion/fireFoam/LES/compartmentFire/system/topoSetDict
index a4c7c7240b0ce9f8a4e6d79df9bdf85eab9cd22d..0f3ab08509c11bbcb0e56cd8b1037fbac090b916 100644
--- a/tutorials/combustion/fireFoam/LES/compartmentFire/system/topoSetDict
+++ b/tutorials/combustion/fireFoam/LES/compartmentFire/system/topoSetDict
@@ -228,19 +228,13 @@ actions
     {
         name    wallPanel;
         type    faceZoneSet;
-        action  delete;
+        action  subtract;
         source  setToFaceZone;
         sourceInfo
         {
             faceSet inletFace;
         }
     }
-
-
-
-
-
-
 );
 
 // ************************************************************************* //
diff --git a/tutorials/compressible/overRhoPimpleDyMFoam/twoSimpleRotors/system/topoSetDict b/tutorials/compressible/overRhoPimpleDyMFoam/twoSimpleRotors/system/topoSetDict
index 1730a01d246c3b8e812f22c8f15cb2721b3b9f79..128937482119a50acb8fb0b74536974053ef829e 100644
--- a/tutorials/compressible/overRhoPimpleDyMFoam/twoSimpleRotors/system/topoSetDict
+++ b/tutorials/compressible/overRhoPimpleDyMFoam/twoSimpleRotors/system/topoSetDict
@@ -59,7 +59,7 @@ actions
     {
         name    c1;
         type    cellSet;
-        action  delete;
+        action  subtract;
         source  cellToCell;
         sourceInfo
         {
diff --git a/tutorials/heatTransfer/chtMultiRegionFoam/externalSolarLoad/system/topoSetDict b/tutorials/heatTransfer/chtMultiRegionFoam/externalSolarLoad/system/topoSetDict
index 446ba1e24bd49b2bd079098703477380c850de64..1928aeb4f189fe07088fd0818c96e7e7eec0cda3 100644
--- a/tutorials/heatTransfer/chtMultiRegionFoam/externalSolarLoad/system/topoSetDict
+++ b/tutorials/heatTransfer/chtMultiRegionFoam/externalSolarLoad/system/topoSetDict
@@ -63,7 +63,7 @@ actions
     {
         name    solid;
         type    cellSet;
-        action  delete;
+        action  subtract;
         source  cellToCell;
         sourceInfo
         {
@@ -108,7 +108,7 @@ actions
     {
         name    solid;
         type    cellSet;
-        action  delete;
+        action  subtract;
         source  cellToCell;
         sourceInfo
         {
diff --git a/tutorials/incompressible/overPimpleDyMFoam/twoSimpleRotors/system/topoSetDict b/tutorials/incompressible/overPimpleDyMFoam/twoSimpleRotors/system/topoSetDict
index 50c273074f068c522aa0adbfd227611ff8002c2f..14957ba5c2a12110b5da32322613e1d587794480 100644
--- a/tutorials/incompressible/overPimpleDyMFoam/twoSimpleRotors/system/topoSetDict
+++ b/tutorials/incompressible/overPimpleDyMFoam/twoSimpleRotors/system/topoSetDict
@@ -59,7 +59,7 @@ actions
     {
         name    c1;
         type    cellSet;
-        action  delete;
+        action  subtract;
         source  cellToCell;
         sourceInfo
         {
diff --git a/tutorials/incompressible/pimpleFoam/RAS/TJunctionFan/system/topoSetDict b/tutorials/incompressible/pimpleFoam/RAS/TJunctionFan/system/topoSetDict
index 62cdff3e629ac966ba7e60cba5535d61f0c354ae..51c370663d5c5fd623adc1d6b7a3d0efb6d098d6 100644
--- a/tutorials/incompressible/pimpleFoam/RAS/TJunctionFan/system/topoSetDict
+++ b/tutorials/incompressible/pimpleFoam/RAS/TJunctionFan/system/topoSetDict
@@ -65,7 +65,7 @@ actions
     {
         name    baffleFaceSet;
         type    faceSet;
-        action  delete;
+        action  subtract;
         source  boxToFace;
         sourceInfo
         {
diff --git a/tutorials/incompressible/simpleFoam/pipeCyclic/system/topoSetDict b/tutorials/incompressible/simpleFoam/pipeCyclic/system/topoSetDict
index 17030d220d5a0f8bdb85c7eaea0c487a4e02b27b..ebf3952fe09a1ec9dea39470b75b706f53a1f037 100644
--- a/tutorials/incompressible/simpleFoam/pipeCyclic/system/topoSetDict
+++ b/tutorials/incompressible/simpleFoam/pipeCyclic/system/topoSetDict
@@ -63,7 +63,7 @@ actions
     {
         name    c0;
         type    cellSet;
-        action  delete;
+        action  subtract;
         source  faceToCell;
         sourceInfo
         {
diff --git a/tutorials/lagrangian/reactingParcelFoam/hotBoxes/createObstacle.setSet b/tutorials/lagrangian/reactingParcelFoam/hotBoxes/createObstacle.setSet
index 59c9f9d9d6bbfbe6d82a764f21031d694a6f06a4..25de4d699aa616a9ba91e3c9618fc6d4ee2cf0f4 100644
--- a/tutorials/lagrangian/reactingParcelFoam/hotBoxes/createObstacle.setSet
+++ b/tutorials/lagrangian/reactingParcelFoam/hotBoxes/createObstacle.setSet
@@ -1,6 +1,6 @@
 cellSet c0 new
 cellSet c0 invert
-cellSet c0 delete boxToCell (0.4 0.1 0.1) (0.6 0.3 0.3)
-cellSet c0 delete boxToCell (0.4 0.1 0.4) (0.6 0.3 0.6)
-cellSet c0 delete boxToCell (0.4 0.4 0.1) (0.6 0.6 0.3)
-cellSet c0 delete boxToCell (0.4 0.4 0.4) (0.6 0.6 0.6)
+cellSet c0 subtract boxToCell (0.4 0.1 0.1) (0.6 0.3 0.3)
+cellSet c0 subtract boxToCell (0.4 0.1 0.4) (0.6 0.3 0.6)
+cellSet c0 subtract boxToCell (0.4 0.4 0.1) (0.6 0.6 0.3)
+cellSet c0 subtract boxToCell (0.4 0.4 0.4) (0.6 0.6 0.6)
diff --git a/tutorials/lagrangian/reactingParcelFoam/hotBoxes/system/topoSetDict b/tutorials/lagrangian/reactingParcelFoam/hotBoxes/system/topoSetDict
index 24195e15d862621d52f1a0c2c16869ddf8de5d04..c60ef73a85c0c752d917b0b01b597f2ae3c6868c 100644
--- a/tutorials/lagrangian/reactingParcelFoam/hotBoxes/system/topoSetDict
+++ b/tutorials/lagrangian/reactingParcelFoam/hotBoxes/system/topoSetDict
@@ -30,7 +30,7 @@ actions
     {
         name    c0;
         type    cellSet;
-        action  delete;
+        action  subtract;
         source  boxToCell;
         sourceInfo
         {
@@ -40,7 +40,7 @@ actions
     {
         name    c0;
         type    cellSet;
-        action  delete;
+        action  subtract;
         source  boxToCell;
         sourceInfo
         {
@@ -50,7 +50,7 @@ actions
     {
         name    c0;
         type    cellSet;
-        action  delete;
+        action  subtract;
         source  boxToCell;
         sourceInfo
         {
@@ -60,7 +60,7 @@ actions
     {
         name    c0;
         type    cellSet;
-        action  delete;
+        action  subtract;
         source  boxToCell;
         sourceInfo
         {
diff --git a/tutorials/mesh/foamyHexMesh/flange/system/faceSetDict b/tutorials/mesh/foamyHexMesh/flange/system/faceSetDict
index 5f3ed0b9a59ab0bbcc738f9cdfdd189b32744cae..4af8cfcb2bf2742dfea0615f28cfbfcf1a8a0001 100644
--- a/tutorials/mesh/foamyHexMesh/flange/system/faceSetDict
+++ b/tutorials/mesh/foamyHexMesh/flange/system/faceSetDict
@@ -18,8 +18,8 @@ FoamFile
 // Name of set to operate on
 name facesToBeRemoved;
 
-// One of (clear | new | invert | add | delete | subset | list)
-action new;
+// One of (add | subtract | subset | clear | new | invert | list)
+action  new;
 
 // Actions to apply to pointSet. These are all the topoSetSource's ending
 // in ..ToFace (see the meshTools library).
diff --git a/tutorials/mesh/foamyHexMesh/flange/system/topoSetDict-background b/tutorials/mesh/foamyHexMesh/flange/system/topoSetDict-background
index 16a72497f13ce7704f23206a704b35a92c4eff3d..7fb6380806c33d05c50e248ef3a4e2d3e737551c 100644
--- a/tutorials/mesh/foamyHexMesh/flange/system/topoSetDict-background
+++ b/tutorials/mesh/foamyHexMesh/flange/system/topoSetDict-background
@@ -23,7 +23,7 @@ FoamFile
 //
 //     // action to perform on set. Two types:
 //     // - require no source : clear/invert
-//     // - require source    : new/add/delete/subset
+//     // - require source    : add/subtract/subset/new
 //     action  new;
 //
 // The source entry varies according to the type of set:
diff --git a/tutorials/mesh/stitchMesh/simple-cube1/system/topoSetDict b/tutorials/mesh/stitchMesh/simple-cube1/system/topoSetDict
index 3604118de25bbb0d285e006051190b46170970e3..754f878051b1ede3ef6bbc9f7e99e039cff29af3 100644
--- a/tutorials/mesh/stitchMesh/simple-cube1/system/topoSetDict
+++ b/tutorials/mesh/stitchMesh/simple-cube1/system/topoSetDict
@@ -56,7 +56,7 @@ actions
     {
         name    inner;
         type    cellSet;
-        action  delete;
+        action  subtract;
         source  cellToCell;
         sourceInfo
         {
@@ -67,7 +67,7 @@ actions
     {
         name    outer;
         type    cellSet;
-        action  delete;
+        action  subtract;
         source  cellToCell;
         sourceInfo
         {
diff --git a/tutorials/multiphase/compressibleInterDyMFoam/laminar/sphereDrop/system/topoSetDict b/tutorials/multiphase/compressibleInterDyMFoam/laminar/sphereDrop/system/topoSetDict
index 04f2b192996133e6628d093ddad39c843fdbc253..15b0923bb7ef588eef50f2cd7cddf477cabf3d02 100644
--- a/tutorials/multiphase/compressibleInterDyMFoam/laminar/sphereDrop/system/topoSetDict
+++ b/tutorials/multiphase/compressibleInterDyMFoam/laminar/sphereDrop/system/topoSetDict
@@ -263,7 +263,7 @@ actions
     {
         name    topBlockCells;
         type    cellSet;
-        action  delete;
+        action  subtract;
         source  cellToCell;
         sourceInfo
         {
diff --git a/tutorials/multiphase/interFoam/laminar/damBreakWithObstacle/createObstacle.setSet b/tutorials/multiphase/interFoam/laminar/damBreakWithObstacle/createObstacle.setSet
index df2efd8a538290488e9924980130264d2ca930ec..6f646d44dc6a6105bfbe716e4d55159bdd4a74a9 100644
--- a/tutorials/multiphase/interFoam/laminar/damBreakWithObstacle/createObstacle.setSet
+++ b/tutorials/multiphase/interFoam/laminar/damBreakWithObstacle/createObstacle.setSet
@@ -1,3 +1,3 @@
 cellSet c0 new
 cellSet c0 invert
-cellSet c0 delete boxToCell (0.375 0.375 0) (0.625 0.625 0.25)
+cellSet c0 subtract boxToCell (0.375 0.375 0) (0.625 0.625 0.25)
diff --git a/tutorials/multiphase/interFoam/laminar/damBreakWithObstacle/system/topoSetDict b/tutorials/multiphase/interFoam/laminar/damBreakWithObstacle/system/topoSetDict
index db9c6783c8d46f50e0b70c76bc6d4c3a6fb948bf..49101640d22dfdc86c8a5e0fd91dba07497d0759 100644
--- a/tutorials/multiphase/interFoam/laminar/damBreakWithObstacle/system/topoSetDict
+++ b/tutorials/multiphase/interFoam/laminar/damBreakWithObstacle/system/topoSetDict
@@ -30,7 +30,7 @@ actions
     {
         name    c0;
         type    cellSet;
-        action  delete;
+        action  subtract;
         source  boxToCell;
         sourceInfo
         {
diff --git a/tutorials/multiphase/interIsoFoam/damBreakWithObstacle/system/topoSetDict b/tutorials/multiphase/interIsoFoam/damBreakWithObstacle/system/topoSetDict
index db9c6783c8d46f50e0b70c76bc6d4c3a6fb948bf..49101640d22dfdc86c8a5e0fd91dba07497d0759 100644
--- a/tutorials/multiphase/interIsoFoam/damBreakWithObstacle/system/topoSetDict
+++ b/tutorials/multiphase/interIsoFoam/damBreakWithObstacle/system/topoSetDict
@@ -30,7 +30,7 @@ actions
     {
         name    c0;
         type    cellSet;
-        action  delete;
+        action  subtract;
         source  boxToCell;
         sourceInfo
         {
diff --git a/tutorials/multiphase/overInterDyMFoam/twoSimpleRotors/system/topoSetDict b/tutorials/multiphase/overInterDyMFoam/twoSimpleRotors/system/topoSetDict
index 6fb992b37a846e2dc759c741455bbc9acfdb3eaa..95d02e89a80433fc2b1444ebf3f4b697aa66261c 100644
--- a/tutorials/multiphase/overInterDyMFoam/twoSimpleRotors/system/topoSetDict
+++ b/tutorials/multiphase/overInterDyMFoam/twoSimpleRotors/system/topoSetDict
@@ -59,7 +59,7 @@ actions
     {
         name    c1;
         type    cellSet;
-        action  delete;
+        action  subtract;
         source  cellToCell;
         sourceInfo
         {