diff --git a/doc/configuration.txt b/doc/configuration.txt
index 7caf5f5..d54459a 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -11418,7 +11418,7 @@
   - suffix match    (-m end) : the patterns are compared with the end of the
     extracted string, and the ACL matches if any of them matches.
 
-  - subdir match    (-m sub) : the patterns are looked up inside the extracted
+  - subdir match    (-m dir) : the patterns are looked up inside the extracted
     string, delimited with slashes ("/"), and the ACL matches if any of them
     matches.