Clarify that predefined strings aren't groff-isms, they're troff-isms.

1 files changed, 1 insertions, 1 deletions

diff --git a/mdoc.7 b/mdoc.7
index 9abb37f1..92fcddb9 100644
--- a/mdoc.7
+++ b/mdoc.7
@@ -149,7 +149,7 @@ recommended for
 which encourages semantic annotation.
 .Ss Predefined Strings
 Historically,
-.Xr groff 1
+troff
 also defined a set of package-specific
 .Dq predefined strings ,
 which, like