diff --git a/gnu/usr.bin/groff/tmac/mdoc.local b/gnu/usr.bin/groff/tmac/mdoc.local
index 8e0b6bea48ed..d46f5db54f3b 100644
--- a/gnu/usr.bin/groff/tmac/mdoc.local
+++ b/gnu/usr.bin/groff/tmac/mdoc.local
@@ -74,6 +74,7 @@
 .ds doc-default-operating-system FreeBSD\~9.0
 .
 .\" FreeBSD releases not found in doc-common
+.ds doc-operating-system-FreeBSD-7.4    7.4
 .ds doc-operating-system-FreeBSD-8.2    8.2
 .ds doc-operating-system-FreeBSD-9.0    9.0
 .