Get posts by Taxonomy without terms

You may do it by this method.

$media_category = get_terms('media_category');
foreach($media_category as $cat) {
    wp_reset_query();
    $args = array('post_type' => 'your_post_type',
        'tax_query' => array(
            array(
                'taxonomy' => 'media_category',
                'field' => 'slug',
                'terms' => $cat->slug,
            ),
        ),
     );
   $loop = new WP_Query($args);
     if($loop->have_posts()) {
      //  echo $cat->name;
        while($loop->have_posts()) : $loop->the_post();
            echo get_the_title();
        endwhile;
     }
}