Those kids who ride around parking lots on their bikes, yelling stuff at cars that pass by or just getting in the way of people driving their cars. Usually prominent on Saturday afternoons, usually about age 13-15.
They ride little tiny bikes that don't fit them, mostly.
Parking Lot Shark: HAY FAT GIRL! Hurrrhurrrhurr. *Laughs with friends*
The act of driving aroundover and over in the same overfilled parking lot to find a spot. If you find your self getting really pissed off and driving recklessly to beat others to a open spot and/or stalking a person walking to their car to imminently take their spot, then your sharking the parking lot.