diff --git a/basis/grouping/grouping.factor b/basis/grouping/grouping.factor
index eb9fd54666..9c849e9b69 100644
--- a/basis/grouping/grouping.factor
+++ b/basis/grouping/grouping.factor
@@ -107,7 +107,7 @@ TUPLE: circular-slice { from read-only } { to read-only } { seq read-only } ;
 
 INSTANCE: circular-slice virtual-sequence
 
-M: circular-slice equal? over slice? [ sequence= ] [ 2drop f ] if ;
+M: circular-slice equal? over circular-slice? [ sequence= ] [ 2drop f ] if ;
 
 M: circular-slice hashcode* [ sequence-hashcode ] recursive-hashcode ;
 
@@ -133,4 +133,4 @@ M: circular-clumps nth
     circular-clumps new-groups ; inline
 
 : circular-clump ( seq n -- array )
-    [ <circular-clumps> ] map-like ; inline
\ No newline at end of file
+    [ <circular-clumps> ] map-like ; inline