When you cram more people in a car than are leagally supposed to be based on seatbelt regulations. This can include people sitting on laps, being locked in the trunk, laying on top of eachother, crammed in so tight that you can't move or your face is pressed up against the window.
It was a rainy day and we needed a ride to the coffee shop so Olivia let us clown car it. Olivia drove, Azelea sat in the passanger seat with Shorty on top of her, Daniel, Mindy, Eric, and about five backpacks were in the back, and Alix was in the trunk with the rest of the backpacks. I jumped in on top of Daniel and Eric and got a little closer to them than I had ever wanted to. The windows were so steamed that the three cops who drove by wouldn't have been able to tell that there were many people in the car at all. We totally clown carred it.