diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 6de67e6484f..a835af1b188 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -1,5 +1,5 @@
 
 
@@ -1075,7 +1075,7 @@ PostgreSQL documentation
        text
        
         Remove the longest string consisting only of characters
-        in characters (or spaces if not supplied)
+        in characters (a space by default)
         from the start and end of string.
        
        btrim('xyxtrimyyx', 'xy')