grease-gun n 1: a hand-operated pump that resembles a revolver; forces grease into parts of a machine [syn: {grease-gun}, {gun}]
grease gun \grease gun\, grease-gun \grease-gun\n. A device held in the hand, having a supply of grease and attached to a reservoir of pressurized air, used to force grease between adjacent moving parts of a machine, especially in the bearings of motor vehicles. [WordNet 1.5 +PJC]