diff --git a/doc/src/sgml/release-17.sgml b/doc/src/sgml/release-17.sgml
index 32e08b79a92..1c1f0c23be2 100644
--- a/doc/src/sgml/release-17.sgml
+++ b/doc/src/sgml/release-17.sgml
@@ -467,7 +467,7 @@ Author: Peter Geoghegan <pg@bowt.ie>
 
 <listitem>
 <para>
-Allow btree indexes to more efficiently find array matches (Peter Geoghegan, Matthias van de Meent)
+Allow btree indexes to more efficiently find a set of values, such as those supplied by IN subqueries (Peter Geoghegan, Matthias van de Meent)
 </para>
 </listitem>