diff --git a/doc/src/sgml/tcn.sgml b/doc/src/sgml/tcn.sgml
index af830dfffec..53c463730cd 100644
--- a/doc/src/sgml/tcn.sgml
+++ b/doc/src/sgml/tcn.sgml
@@ -18,7 +18,7 @@
  </para>
 
  <para>
-  Only one parameter may be suupplied to the function in a
+  Only one parameter may be supplied to the function in a
   <literal>CREATE TRIGGER</> statement, and that is optional.  If supplied
   it will be used for the channel name for the notifications.  If omitted
   <literal>tcn</> will be used for the channel name.