Remove category description

function removecategorydescrption($columns)
{
 // only edit the columns on the current taxonomy
 if ( !isset($_GET['taxonomy']) || $_GET['taxonomy'] != 'category' )
 return $columns;

 // unset the description columns
 if ( $posts = $columns['description'] ){ unset($columns['description']); }

 return $columns;
}
add_filter('manage_edit-category_columns','removecategorydescrption');