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.
... in mock deprecation. "You're beginning to fit into the local merchant pattern better than the real thing. However, just for the record, I had this, ah, grease gun, trained ... — Adaptation • Dallas McCord Reynolds