diff --git a/docs/source/customize.rst b/docs/source/customize.rst
index 1d976d1..e7ce2ec 100644
--- a/docs/source/customize.rst
+++ b/docs/source/customize.rst
@@ -155,7 +155,7 @@ can be added to the list of known words for just that document.
 
 ::
 
-  .. spelling::
+  .. spelling:word-list::
 
      Docutils
      Goodger