diff --git a/Lib/UserList.py b/Lib/UserList.py
index 7bd0298..d4a8d2f 100644
--- a/Lib/UserList.py
+++ b/Lib/UserList.py
@@ -4,7 +4,7 @@
     def __init__(self, initlist=None):
         self.data = []
         if initlist is not None:
-            # XXX should this accept an arbitary sequence?
+            # XXX should this accept an arbitrary sequence?
             if type(initlist) == type(self.data):
                 self.data[:] = initlist
             elif isinstance(initlist, UserList):