diff --git a/runtime/autoload/dist/ft.vim b/runtime/autoload/dist/ft.vim
index 0cbcb1b..74df871 100644
--- a/runtime/autoload/dist/ft.vim
+++ b/runtime/autoload/dist/ft.vim
@@ -231,7 +231,7 @@
 	  \ || line =~ '^\s*: \S'
       setf forth
     else
-      setf fs
+      setf fsharp
     endif
   endif
 endfunc