diff --git a/src/testdir/test_startup.vim b/src/testdir/test_startup.vim
index 2185b4d..bce431f 100644
--- a/src/testdir/test_startup.vim
+++ b/src/testdir/test_startup.vim
@@ -216,7 +216,7 @@
   endif
 
   let save_term = $TERM
-  let $TERM = 'unknown'
+  let $TERM = 'unknownxxx'
   let out = system(GetVimCommand() . ' -c''set term'' -c cq')
   call assert_match("defaulting to 'ansi'", out)
   let $TERM = save_term