diff --git a/lib/linguist/languages.yml b/lib/linguist/languages.yml
index 09f4641c..a2e470fd 100644
--- a/lib/linguist/languages.yml
+++ b/lib/linguist/languages.yml
@@ -320,6 +320,8 @@ Diff:
 DOT:
   type: programming
   primary_extension: .dot
+  extensions:
+  - .gv
 
 Dylan:
   type: programming