diff --git a/runtime/doc/syntax.txt b/runtime/doc/syntax.txt
index afad175..0fd9769 100644
--- a/runtime/doc/syntax.txt
+++ b/runtime/doc/syntax.txt
@@ -5042,7 +5042,8 @@
 LineNr		Line number for ":number" and ":#" commands, and when 'number'
 		or 'relativenumber' option is set.
 							*hl-CursorLineNr*
-CursorLineNr	Like LineNr when 'cursorline' or 'relativenumber' is set for
+CursorLineNr	Like LineNr when 'cursorline' is set and 'cursorlineopt' is
+		set to "number" or "both", or 'relativenumber' is set, for
 		the cursor line.
 							*hl-MatchParen*
 MatchParen	The character under the cursor or just before it, if it