diff --git a/contrib/sendmail/vacation/vacation.1 b/contrib/sendmail/vacation/vacation.1
index e03f19ccf27f..ed59610f5830 100644
--- a/contrib/sendmail/vacation/vacation.1
+++ b/contrib/sendmail/vacation/vacation.1
@@ -59,7 +59,7 @@ Available options:
 .TP
 .BI \-a " alias"
 Handle messages for
-.Ar alias
+.I alias
 in the same manner as those received for the user's
 login name.
 .TP