diff --git a/man7/user_namespaces.7 b/man7/user_namespaces.7
index f8224bdda..9e1e9642c 100644
--- a/man7/user_namespaces.7
+++ b/man7/user_namespaces.7
@@ -1045,6 +1045,12 @@ to gain more privilege than the root user of a user namespace has.
 .\"
 .\" ============================================================
 .\"
+.SS Global root
+The term "global root" is sometimes used as a shorthand for
+user ID 0 in the initial user namespace.
+.\"
+.\" ============================================================
+.\"
 .SS Availability
 Use of user namespaces requires a kernel that is configured with the
 .B CONFIG_USER_NS