coding/patterns/dictionary.md

@@ -21,7 +21,7 @@ const vector dirn(dict.get<vector>("direction"));
 
 - These retrieve values with input checking on type and excess tokens.
 
-**Anti-pattern**: using dictionary `lookup()` returns an stream,
+**Anti-pattern**: using dictionary `lookup()` returns a stream,
 which needs additional handling for primitives and does not incorporate
 input checking:
 ```