Fix typo (from SF bug #1086127).
diff --git a/Doc/lib/libos.tex b/Doc/lib/libos.tex
index 402f678..d69c11c 100644
--- a/Doc/lib/libos.tex
+++ b/Doc/lib/libos.tex
@@ -1820,7 +1820,7 @@
 
 \begin{datadesc}{pathsep}
 The character conventionally used by the operating system to separate
-search patch components (as in \envvar{PATH}), such as \character{:} for
+search path components (as in \envvar{PATH}), such as \character{:} for
 \POSIX{} or \character{;} for Windows.
 Also available via \module{os.path}.
 \end{datadesc}