diff --git a/core/vocabs/vocabs.factor b/core/vocabs/vocabs.factor
index 5067d88f50..edffd079c8 100644
--- a/core/vocabs/vocabs.factor
+++ b/core/vocabs/vocabs.factor
@@ -25,7 +25,7 @@ ERROR: bad-vocab-name name ;
 
 : check-vocab-name ( name -- name )
     dup string? [ bad-vocab-name ] unless
-    dup ":/\\ " intersects? [ bad-vocab-name ] when ;
+    dup [ ":/\\ " member? ] any? [ bad-vocab-name ] when ;
 
 TUPLE: vocab-link name ;