diff --git a/src/reflect/type.go b/src/reflect/type.go
index dce40582bb..9c967de45c 100644
--- a/src/reflect/type.go
+++ b/src/reflect/type.go
@@ -32,7 +32,8 @@ import (
 // calling kind-specific methods. Calling a method
 // inappropriate to the kind of type causes a run-time panic.
 //
-// Type values are comparable, such as with the == operator.
+// Type values are comparable, such as with the == operator, and Type can be
+// used as a map key type.
 // Two Type values are equal if they represent identical types.
 type Type interface {
 	// Methods applicable to all types.