Unnecessary buttons in the Visual Editor? Try this
add_filter('mce_buttons', 'remove_mce_buttons' ); function remove_mce_buttons($buttons) { unset($buttons[16]); return $buttons; } // [0] => bold // [1] => italic // [2] => strikethrough // [3] => | // [4] => bullist // [5] => numlist // [6] => blockquote // [7] => | // [8] => justifyleft // [9] => justifycenter // [10] => justifyright // [11] => | // [12] => link // [13] => unlink // [14] => wp_more // [15] => | // [16] => spellchecker // [17] => fullscreen // [18] => wp_adv
If you’re concerned about accidentally removing the wrong one, it’s simple enough to add a check
add_filter('mce_buttons', 'remove_mce_buttons' ); function remove_mce_buttons($buttons) { if ($buttons[16] == 'spellchecker') unset($buttons[16]); return $buttons; }