#1934: fix os.path.isabs docs.
diff --git a/Doc/library/os.path.rst b/Doc/library/os.path.rst
index 125044d..05eed8a 100644
--- a/Doc/library/os.path.rst
+++ b/Doc/library/os.path.rst
@@ -144,7 +144,9 @@
.. function:: isabs(path)
- Return ``True`` if *path* is an absolute pathname (begins with a slash).
+ Return ``True`` if *path* is an absolute pathname. On Unix, that means it
+ begins with a slash, on Windows that it begins with a backslash after chopping
+ off a potential drive letter.
.. function:: isfile(path)