diff --git a/core/classes/singleton/singleton.factor b/core/classes/singleton/singleton.factor
index 02ca405145..b70e3e074a 100644
--- a/core/classes/singleton/singleton.factor
+++ b/core/classes/singleton/singleton.factor
@@ -1,8 +1,8 @@
 ! Copyright (C) 2008, 2010 Doug Coleman, Slava Pestov.
 ! See http://factorcode.org/license.txt for BSD license.
 USING: classes classes.algebra classes.algebra.private
-classes.predicate classes.predicate.private kernel sequences
-words ;
+classes.predicate classes.predicate.private definitions kernel
+sequences words ;
 IN: classes.singleton
 
 <PRIVATE
@@ -25,4 +25,7 @@ M: singleton-class (classes-intersect?)
     over singleton-class? [ eq? ] [ call-next-method ] if ;
 
 M: singleton-class predicate-quot
-    singleton-predicate-quot ;
\ No newline at end of file
+    singleton-predicate-quot ;
+
+M: singleton-class definer
+    drop \ SINGLETON: f ;