diff --git a/mercurial/help/glossary.txt b/mercurial/help/glossary.txt
index 340d047ea577d11e60c374ad823500641aef235f_bWVyY3VyaWFsL2hlbHAvZ2xvc3NhcnkudHh0..8298d220cbf914bb4bab6c5ee2a483ca3d015499_bWVyY3VyaWFsL2hlbHAvZ2xvc3NhcnkudHh0 100644
--- a/mercurial/help/glossary.txt
+++ b/mercurial/help/glossary.txt
@@ -237,6 +237,9 @@
     closed when all its heads are closed and consequently is not
     listed by :hg:`branches`.
 
+    Closed heads can be re-opened by committing new changeset as the
+    child of the changeset that marks a head as closed.
+
 Head, repository
     A topological head which has not been closed.