remove-url-fild.php

<?php
/**-------------------------------------------
* @package Code Snippets
* @link http://rhythmshahriar.com/code/
* @author Rhythm <[email protected]>
* @copyright Copyright (c) 2013, Rhythm Shahriar
-------------------------------------------------*/

add_filter('comment_form_default_fields', 'rs_remove_comment_web_url');
function rs_remove_comment_web_url($fields)
{
  if(isset($fields['url']))
   unset($fields['url']);
  return $fields;
}