Green’s Dictionary of Slang

1. (orig. US) a pistol or revolver.

1897		J. London ‘The Road’ in Hendricks & Shepherd Jack London Reports (1970) 311–21: Their argot is peculiar study. [...] gat, gun.
1904		Number 1500 Life In Sing Sing 248: Gatt. A revolver.
1911		D. Runyon ‘The Informal Execution of Soupbone Pew’ in From First to Last (1954) 69: ‘He was there forty ways with a sap and gat, and he’d shoot as quick as he’d slug.’.
1914		J. McCree ‘Types’ Variety Stage Eng. Plays 🌐 I have frisked him for his rod and gat and fanned him for his chiv.
1922		Capitol Times (Madison, WI) 16 May 9/3: ‘Me an’ this here old gatt has went through some tough times together’.
1923		Wodehouse Leave it to Psmith (1993) 515: You’re going to stick up this bozo [...] with a gat.
1929		W.R. Burnett Little Caesar (1932) 40: Get out your gat, Tony.
1931		C.B. Yorke ‘Snowbound’ in Gangster Stories Oct. n.p.: Queen Sue was the toughest moll that ever pulled a gat this side of Hades.
1931		Eve. News (Rockhampton, Qld) 27 May 3/1: A revolver is called a ‘gat’ in many circles; and the Americanisms, ‘spade’ (a negro) and ‘broad’ (a woman) are commonly used in Sydney.
1933		‘Goat’ Laven Rough Stuff 160: They could prove that there were three gats in the car that belonged to somebody.
1943		D. Burley N.Y. Amsterdam News 30 Oct. B8: Those zoot-suited bandits armed with gats.
1943		J. Binning Target Area 52: He drew his gat, that faithful pal, and let Red Jim have it between the eyes.
1950		S.J. Baker in Sun. Herald (Sydney) 8 June 9/4: Among American borrowings recorded in Detective Doyle's list are: [...] ‘broads,’ playing cards; ‘gat,’ a gun; ‘gimmick,’ a house breaking instrument [etc].
1955		B. Appel Tough Guy [ebook] He’ll get stinko, come for you and there’ll be no crowd to take his gat away like at Killigan’s.
1958		Willans & Searle Complete Molesworth (1985) 27: You could think they would put a gat or a germ gun to their heads.
1960		Wodehouse Jeeves in the Offing 15: Seldom cashes a cheque at his bank without producing a gat and saying, ‘This is a stick-up’.
1964		R. Abrahams Deep Down In The Jungle 157: I ran over to Lombard Street to get my gat.
1971		N. Smith Gumshoe (1998) 58: I’d made my play, displayed my gat and got a fat nothing in response.
1987		King Tee & Mixmaster Spade ‘Ya Better Bring a Gun’ 🎵 Everytime that you see me I’m tearin a gat / I got .380s and .22s / You messs with me, I’m gonna bust on you / I got a .357 and a M-16.
1993		Dr Dre ‘Deeez Nuuuts’ 🎵 Long Beach, tic tac, grab your gat, watch your back.
2000		T. Udo Vatican Bloodbath 93: The gun-wielding clerics all looked at their feet, mumbled and turned red...Slowly they stashed their gats back in their cassocks.
2001		(con. 1990s) in J. Miller One of the Guys 141: ‘Y’all have to have y’all’s gats and stuff ready’.
2001		D. Looser Boobslang [U. Canterbury D.Phil. thesis] 76/2: gat n. 1a firearm.
2011		G. Hayward Corruption Officer [ebk] cap. 16: These fools done fucked around and let a nigga purchase a firearm! It’s a gat, a ratchet, a biscuit, a burner to all my inner-city home boys and a ooohhwop to anybody over fifty.
2014		Stormzy ‘Shut Up’ 🎵 If you got a G-A-T bring it out.
2020		S.A. Crosby Blacktop Wasteland 75: ‘I got the gat, so I make the rules’.

2. (US) a gunman.

1930

J.P. McEvoy Hollywood Girl 106: Mike the Rat and Gyp the Gat.

3. (US prison) a knife made in prison.

2000

Other Side of the Wall: Prisoner’s Dict. July 🌐 Gat: Shank. A prison made knife. (IL).