diff --git a/reference/image/functions/imagexbm.xml b/reference/image/functions/imagexbm.xml
index bb2d208bc9..7a0effca8c 100644
--- a/reference/image/functions/imagexbm.xml
+++ b/reference/image/functions/imagexbm.xml
@@ -3,7 +3,7 @@
 <refentry xml:id="function.imagexbm" xmlns="http://docbook.org/ns/docbook">
  <refnamediv>
   <refname>imagexbm</refname>
-  <refpurpose>Output XBM image to browser or file</refpurpose>
+  <refpurpose>Output an XBM image to browser or file</refpurpose>
  </refnamediv>
  <refsect1 role="description">
   &reftitle.description;