diff --git a/Doc/library/os.rst b/Doc/library/os.rst
index 2149ae5..71133c4 100644
--- a/Doc/library/os.rst
+++ b/Doc/library/os.rst
@@ -257,7 +257,7 @@
 
    .. index:: single: user; id
 
-   Return the current process's user id.
+   Return the current process's real user id.
 
    Availability: Unix.