diff --git a/Doc/library/os.rst b/Doc/library/os.rst
index b2d8f80..6964183 100644
--- a/Doc/library/os.rst
+++ b/Doc/library/os.rst
@@ -717,7 +717,8 @@
    combined using the bitwise OR operator ``|``. Availability: Windows.
 
 
-.. data:: O_DIRECT
+.. data:: O_ASYNC
+          O_DIRECT
           O_DIRECTORY
           O_NOFOLLOW
           O_NOATIME