gaff (Noun) — A sharp metal spike or spur that is fastened to the leg of a gamecock.
gaff (Noun) — A spar rising aft from a mast to support the head of a quadrilateral fore-and-aft sail.
gaff (Noun) — An iron hook with a handle; used for landing large fish.
gaff (Noun) — (informal) someone's building (house, shop, etc).