WordPress tip: Modify any role name to fit your needs

Simply paste this code into your function.php file. Edit lines 5 and 6 at your convenience.

function wps_change_role_name() {
    global $wp_roles;
    if ( ! isset( $wp_roles ) )
        $wp_roles = new WP_Roles();
    $wp_roles->roles['contributor']['name'] = 'Owner';
    $wp_roles->role_names['contributor'] = 'Owner';
}
add_action('init', 'wps_change_role_name');

Thanks to Kevin Chard for the tip!!