Green’s Dictionary of Slang

1. (US) a gun, thence a pistol.

1836		D. Crockett Exploits and Adventures (1934) 144: I squared myself, raised my beautiful Betsey to my shoulder, took deliberate aim, and smack I sent the bullet right into the centre of the bull’s eye.
1843		R. Carlton New Purchase I 174: I’ll jist take old Bet — (a rifle).
1845		W.T. Thompson Chronicles of Pineville 169: Old Betsey here toats fifteen buckshot and a ball, and slings ’em to kill.
1856		Spirit of Age (Sacramento, CA) 4 Nov. 3/1: Jest let them raise that check agin me, and if I don’t shoot why old Betsy won’t blizzard [DA].
1869		New North West (Deer Lodge, MT) 20 Aug. 2/7: Mr Fredericks proceeded immediately on the horse, loaded ‘Betsey’, (his shot gun) [DA].
1870		Times-Picayune (New Orleans, LA) 19 June 11/4: And so my old gun Bet is busted, / Both on us gone, worn down,, and rusted.
1878–9		A. Garcia Tough Trip Through Paradise (1977) 66: Beaver Tom had nothing to do but look wise and hold his Betsy Ann, a buffalo gun. [Ibid.] 105: Betsy Jane went off with a roar.
1887		G. Devol Forty Years a Gambler 38: I pulled out old ‘Betsey Jane,’ one of the best tarantula pistols in the Southern county.
1892		J.C. Duval Young Explorers 24: I picked up ‘Old Bess,’ my double-barrel shotgun.
1895		P.H. Emerson Marsh Leaves 137: Potter had a long-barrelled gun, his ‘old Bessy’, and I took my eyes along with me .
1922		(con. mid-19C) A. Gonzales Black Border 83: He had implicit faith and infinite pride in the shooting powers of his old ‘muskick,’ – ‘Ole Betsey, him cya’ shot fuh sowl!’.
1922		(con. late 19C) V. Hemphill Down the Mother Lode 17: Among the handful of coins and small nuggets he brought from his pocket was a bullet strung on a bit of dirty twine. ‘Ah! a love token, senor?’ ‘Yes, from the throat of Betsy Jane’ (a term often used for a rifle).
1927		J.F. Dobie Texas and Southwestern Lore 51: Uncle Billy jerked ‘old Betsy’ (his rifle) up to his shoulder.
1937		E. Anderson Thieves Like Us (1999) 39: [of a shotgun] I’ll still take old Betsy.
1944		D. Runyon Runyon à la Carte 1: He says he will go out and borrow a Betsy off of Officer Gloon and blow the parrot’s brains out.
1951		M. Spillane One Lonely Night 76: I blew the dust off old Betsy.
1960, 1975		Wentworth & Flexner DAS.
1965		J.P. Carstairs Concrete Kimono 48: ‘You’ve noticed I’m toting a Betsy.’ ‘Betsy?’ ‘Equalizer, rod, gat, iron.’.
2001		D. Looser Boobslang [U. Canterbury D.Phil. thesis] 16/1: Betsy n. a firearm.

2. an effeminate man.

1849		Sam Sly 3 Feb. 7/1: Sam Sly Never Said [...] That Fred G——d [...] nurses a babby; or that his father is an office-scrubber, window cleaner, and Betsey in general.
1860		R. Nicholson Rogue’s Progress (1966) 96: The captain’s elegant appearance and handsome person became the talk among the inmates of the jail, and some low blackguards made a set of annoyance [...] calling after him ‘Betsy Bailey’.

3. see betty n. (3)