In wprentals-core plugin – file wprentals-core.php you have this WordPress action

add_action(‘wp_head’, ‘wpestate_add_custom_meta_to_header’);
In the function of this action you have various meta tags for some situation.
To remove the description tag for taxonomy just remove the line 293
 print '<meta name="description" content="'.strip_tags( term_description('', get_query_var( 'taxonomy' ) )).'" >';
Or you can populate the term description in wp-admin -> properties -> categories -> edit category and that description will be used as a meta description.