diff --git a/builtin/commit.c b/builtin/commit.c
index 1dfd799..505fe60 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -1507,7 +1507,7 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
 		OPT_STRING(0, "fixup", &fixup_message, N_("commit"), N_("use autosquash formatted message to fixup specified commit")),
 		OPT_STRING(0, "squash", &squash_message, N_("commit"), N_("use autosquash formatted message to squash specified commit")),
 		OPT_BOOL(0, "reset-author", &renew_authorship, N_("the commit is authored by me now (used with -C/-c/--amend)")),
-		OPT_BOOL('s', "signoff", &signoff, N_("add Signed-off-by:")),
+		OPT_BOOL('s', "signoff", &signoff, N_("add a Signed-off-by trailer")),
 		OPT_FILENAME('t', "template", &template_file, N_("use specified template file")),
 		OPT_BOOL('e', "edit", &edit_flag, N_("force edit of commit")),
 		OPT_CLEANUP(&cleanup_arg),