Pistoning

Part of speech: verb

Definitions

1. Performing a repetitive motion by moving forward and backward similar to the action of a piston
2. Engaging in a to-and-fro movement that resembles the push-and-pull function of a piston within a cylinder
3. Executing a cyclical sliding action characterized by continuous forward and backward shifts like that of a piston

Etymology: The word "piston" entered English by way of French, where "piston" meant a pestle or pounding tool, and it is from that sense of pounding up and down that the mechanical part took its name. The verb "pistoning", the continuous form of "to piston," is simply what happens when a piston moves: it drives back and forth inside a cylinder, which is why the verb means to thrust back and forth in that same rapid, repeated motion.