diff --git a/Lib/os.py b/Lib/os.py
index 7c49ba4b6a4..31002acb75b 100644
--- a/Lib/os.py
+++ b/Lib/os.py
@@ -1,4 +1,4 @@
-r"""OS routines for Mac, DOS, NT, or Posix depending on what system we're on.
+r"""OS routines for Mac, NT, or Posix depending on what system we're on.
 
 This exports:
   - all functions from posix, nt, os2, mac, or ce, e.g. unlink, stat, etc.