diff --git a/lib/linguist/languages.yml b/lib/linguist/languages.yml
index 3e020d65..ab842d3f 100755
--- a/lib/linguist/languages.yml
+++ b/lib/linguist/languages.yml
@@ -2466,6 +2466,7 @@ Markdown:
   - ".md"
   - ".markdown"
   - ".mdown"
+  - ".mdwn"
   - ".mkd"
   - ".mkdn"
   - ".mkdown"