Edit The WordPress Meta Widget

Do you really want the link to WordPress sitting in your Admin/Meta widget? If not, open up the default-widgets.php file in the wp-includes directory.

Make a copy of it.

Go to the <ul> tag which is around line 295 and remove this <li> code:

<li><a href=”http://wordpress.org/” title=”<?php echo esc_attr(__(‘Powered by WordPress, state-of-the-art semantic personal publishing platform.’)); ?>”>WordPress.org</a></li>

You can trim out more if you want, before saving the file.