diff --git a/lib/moodlelib.php b/lib/moodlelib.php
index 41ab9365797..9f0415940aa 100644
--- a/lib/moodlelib.php
+++ b/lib/moodlelib.php
@@ -117,7 +117,7 @@ define('PARAM_BOOL',     'bool');
 define('PARAM_CAPABILITY',   'capability');
 
 /**
- * PARAM_CLEANHTML - cleans submitted HTML code and removes slashes. It stays as HTML.
+ * PARAM_CLEANHTML - cleans submitted HTML code. use only for text in HTML format. It stays as HTML.
  */
 define('PARAM_CLEANHTML', 'cleanhtml');