diff --git a/django/db/backends/__init__.py b/django/db/backends/__init__.py
index 06ce9deb72..9afc143460 100644
--- a/django/db/backends/__init__.py
+++ b/django/db/backends/__init__.py
@@ -792,7 +792,7 @@ class BaseDatabaseOperations(object):
         This is used on specific backends to rule out known aggregates
         that are known to have faulty implementations. If the named
         aggregate function has a known problem, the backend should
-        raise NotImplemented.
+        raise NotImplementedError.
         """
         pass