diff --git a/docs/manual/makeusers-syntax.txt b/docs/manual/makeusers-syntax.txt
index 5b3f34777..ecf3eb040 100644
--- a/docs/manual/makeusers-syntax.txt
+++ b/docs/manual/makeusers-syntax.txt
@@ -16,7 +16,8 @@ user per line; the fields are:
 Where:
 
 - +username+ is the desired user name (aka login name) for the user.
-  It can not be +root+, and must be unique.
+  It can not be +root+, and must be unique. If set to +-+, then just a
+  group will be created.
 - +uid+ is the desired UID for the user. It must be unique, and not
   +0+. If set to +-1+, then a unique UID will be computed by Buildroot
   in the range [1000...1999]