The act of taking a shit in a semi-public area (i.e. alley, sidewalk), transporting it and leaving it on the floorboard of the nearest unlocked car.
"Dude, I just made a Dump Truck Deposit in that mitsubishi outlander. There was some chick passed out in the seat, but I don't think she noticed."
by stinkassnixon March 12, 2010