diff --git a/basis/disjoint-sets/disjoint-sets-tests.factor b/basis/disjoint-sets/disjoint-sets-tests.factor
index cb9233343e..92fd2b26ce 100644
--- a/basis/disjoint-sets/disjoint-sets-tests.factor
+++ b/basis/disjoint-sets/disjoint-sets-tests.factor
@@ -1,5 +1,5 @@
 USING: tools.test disjoint-sets namespaces slots.private ;
-IN: disjoint-sets.testes
+IN: disjoint-sets.tests
 
 SYMBOL: +blah+
 -405534154 +blah+ 1 set-slot