diff --git a/src/testdir/test_substitute.vim b/src/testdir/test_substitute.vim
index a2367cd..afdc104 100644
--- a/src/testdir/test_substitute.vim
+++ b/src/testdir/test_substitute.vim
@@ -174,8 +174,8 @@
   bwipe!
 endfunc
 
-" Test :s with ? as separator.
-func Test_substitute_question_separator()
+" Test :s with ? as delimiter.
+func Test_substitute_question_delimiter()
   new
   call setline(1, '??:??')
   %s?\?\??!!?g