diff --git a/doc/w3m.1 b/doc/w3m.1
index 95193cc..0781bb9 100644
--- a/doc/w3m.1
+++ b/doc/w3m.1
@@ -85,8 +85,8 @@ automatically render frame
 .B -dump
 dump formatted page into stdout
 .TP
-.B -cols width
-specify column width (used with -dump)
+.B -cols num
+with stdout as destination; HTML is rendered to lines of \fInum\fR characters
 .TP
 .B -ppc count
 specify the number of pixels per character (4.0...32.0).