diff --git a/dlib/dir_nav/dir_nav_extensions_abstract.h b/dlib/dir_nav/dir_nav_extensions_abstract.h
index e4056fe39..d693a6bc5 100644
--- a/dlib/dir_nav/dir_nav_extensions_abstract.h
+++ b/dlib/dir_nav/dir_nav_extensions_abstract.h
@@ -30,7 +30,7 @@ namespace dlib
     );
     /*!
         ensures
-            - if (a directory with the given filename exists) then
+            - if (a directory with the given dirname exists) then
                 - returns true
             - else
                 - returns false