A thing you do driving which includes you turning a right on the street you are driving on, then taking another right, and another, and another, so you are making a "box." Often used when you think some one is tailing you. If the person behind you is still following you, drive to a crowded, lighted area and call 911.
"Man, I think there's a serial killer trying to follow us home."
"Oh, use The Box. Just in case...."