gaff / gaffe are similar-sounding terms with different meanings (referred to as homophones). To better understand the differences, see below for definitions, pronunciation guides, and example sentences using each term. 👇
gaff: (noun) a sharp metal spike or spur that is fastened to the leg of a gamecock. (noun) a spar rising aft from a mast to support the head of a quadrilateral fore-and-aft sail. (noun) an iron hook with a handle; used for landing large fish.
gaffe: NA
gaff: g·AE·f
gaffe: g·AE·f
(Examples are Wikipedia snippets under the CC ShareAlike 3.0 license. Definitions drawn from WordNet.)