diff --git a/doc/source/whatsnew/v0.23.2.txt b/doc/source/whatsnew/v0.23.2.txt
index a41a6c31b0678..9c4b408a1d24b 100644
--- a/doc/source/whatsnew/v0.23.2.txt
+++ b/doc/source/whatsnew/v0.23.2.txt
@@ -61,8 +61,8 @@ Fixed Regressions
 Performance Improvements
 ~~~~~~~~~~~~~~~~~~~~~~~~
 
-- Improved performance of membership checks in :class:`CategoricalIndex`
-  (i.e. ``x in ci``-style checks are much faster). :meth:`CategoricalIndex.contains`
+- Improved performance of membership checks in :class:`Categorical` and :class:`CategoricalIndex`
+  (i.e. ``x in cat``-style checks are much faster). :meth:`CategoricalIndex.contains`
   is likewise much faster (:issue:`21369`, :issue:`21508`)
 - Improved performance of :meth:`HDFStore.groups` (and dependent functions like
   :meth:`~HDFStore.keys`.  (i.e. ``x in store`` checks are much faster)