When you are doing a girl from behind, preferably close to the edge of the bed, and you grab her by the shoulders and lift her up. This results in her swinging her arms aimlessly like a T-Rex while making moaning noises.
A cheap ass. The person, who at dinner in a restaraunt when its tip time, whos arms seem to be too short to reach into their wallet and tip their fair share. T rexes, frequently seen reusing napkins and relying heavily on the "if its yellow, let it mellow" flushing principal, are the utmost cheapest, tight waded, penny pinching bastards around.