diff --git a/Doc/library/os.rst b/Doc/library/os.rst
index 6964183ca02..a85a04cc72e 100644
--- a/Doc/library/os.rst
+++ b/Doc/library/os.rst
@@ -2031,7 +2031,7 @@ Miscellaneous System Information
 
    Return the number of processes in the system run queue averaged over the last
    1, 5, and 15 minutes or raises :exc:`OSError` if the load average was
-   unobtainable.
+   unobtainable.  Availability: Unix.
 
    .. versionadded:: 2.3