A sexual act in which the male performs a reverse titty fuck so his ass and balls are over her face. The males balls then rub up and down her face making the motion of machines cleaning a car at a car wash.
I totally car washed a girl last night. My balls smacked her face so hard!
When one takes his car and drives it into a tunnel, equipped with motorized and automatic machines such as brushes and sponges. Also, there are sprays in which soap comes out to help make the car cleaner. At the end of the "carwash" the car undergoes a drying process, making the car dry from all of the soap and water used earlier to make the car clean. The main purpose of a carwash is to make the car clean. Most car-drivers get a car wash every month or so. However, some people who love their car will get one every week.
John: Woah! That car of yours is very clean! What did you do it?
Pete: Last night, I brought it to get a carwash. It was quite satisfying.