diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index b21c433565..425544ae50 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -1295,9 +1295,6 @@
 
       <row>
        <entry>
-        <indexterm>
-         <primary>trim</primary>
-        </indexterm>
         <literal><function>trim(<optional>leading | trailing
         | both</optional> <optional>from</optional>
         <parameter>string</parameter>