diff --git a/src/backend/optimizer/plan/setrefs.c b/src/backend/optimizer/plan/setrefs.c
index cc8d39f39bb..623b8863cc5 100644
--- a/src/backend/optimizer/plan/setrefs.c
+++ b/src/backend/optimizer/plan/setrefs.c
@@ -1055,7 +1055,7 @@ copyVar(Var *var)
  * This is code that is common to all variants of expression-fixing.
  * We must look up operator opcode info for OpExpr and related nodes,
  * add OIDs from regclass Const nodes into root->glob->relationOids, and
- * add catalog TIDs for user-defined functions into root->glob->invalItems.
+ * add catalog OIDs for user-defined functions into root->glob->invalItems.
  *
  * We assume it's okay to update opcode info in-place.  So this could possibly
  * scribble on the planner's input data structures, but it's OK.