// This theme uses wp_nav_menu() in two locations.
register_nav_menus( array(
    'primary'   => __( 'Top primary menu', 'twentyfourteen' ),
    'secondary' => __( 'Secondary menu in left sidebar', 'twentyfourteen' ),
) );

register_nav_menus( array(
    'primary'   => __( 'Top primary menu')
    ) );

__( 'Top primary menu', 'twentyfourteen' )