1. To stop following directly behind one, especially in a car. I wish this guy would get off my bumper! I'm going the speed limit, for crying out loud! Get off my bumper, Jim—you keep ramming into me!

2. By extension, to stop pestering or closely observing one. Often used as an imperative. The boss keeps checking in every half hour to see how the project is coming along. I wish he would get off our bumper! Would you get off my bumper, kids? I'm trying to concentrate here.