Green’s Dictionary of Slang

1. (orig. US) a left-handed person or a nickname for one who is left-handed; thus lefty adv., with the left hand.

1897		R.W. Chambers Mystery of Choice 188: Ask Lefty Sawyer; ask Dyce; ask Carrots. — He’s got to swing fur it — ain’t he, Tully?
1907		Outing Mag. 50 181/2: Lefty Allen of the O-Bar-O, sang in his sweet tenor.
1912		Bulletin (Sydney) 26 Sept. 15/1: This Lefty Green is jest a cow!
1914		W. Hoban Jerry on the Job 29 May [synd. cartoon strip] Maybe I ain’t doin’ right by ‘Lefty’. He ain’t a bad guy.
1927		‘Max Brand’ Pleasant Jim 113: Go handle that fellow, Lefty!
1933		J. Spenser Limey 218: A man named Lefty Mason.
1947		N. Algren Neon Wilderness (1986) 75: C’mon Lefty, tell us about it.
1958		R. Chandler Playback 42: He was a lefty.
1961		T. Ronan Only a Short Walk 120: Lefty Williams ’s just another mug bush punter.
a.1986		‘Old Zebra Dun’ in G. Logsdon Whorehouse Bells Were Ringing (1995) 83: Well, I heard ol’ Lefty snicker, and the first to speak was Sam.
2006		F.X. Toole Pound for Pound 74: The guy knew how to handle a lefty.

2. a person who has lost their limbs on their left side (arm and leg).

1918		‘A-No. 1’ Mother of the Hoboes 43: The Rating Of The Tramps. 19 Lefty: train rider who lost left arm and leg.
1923		N. Anderson Hobo 100: [From A No. 1, The Famous Tramp] 19. Lefty. Train rider who lost left arm and leg.
1931		Irwin Amer. Tramp and Und. Sl. 120: Lefty. – One minus a left arm or hand.
1949		Monteleone Criminal Sl. (rev. edn) 144: lefty One with a left leg or arm missing.
1965		B. Jackson Get Your Ass in the Water (1974) 85: I’ll tell you the story of a notorious pickpocket, who name was Limpty Lefty McCree.

3. (also lefto) a left-wing political radical.

1935		C. Odets Waiting for Lefty Act I: Where’s your pal, Lefty?
1952		Lait & Mortimer USA Confidential 92: It is loaded with pinks, lefties, union overlords, and those who serve the underworld.
1967		K. Amis letter 25 July in Leader (2000) 683: If top Lefties could be shown to be suffering in some way under the Wilson regime.
1972		G.W. Turner Eng. Lang. in Aus. and N.Z. 101: Lefto ‘a left winger’.
1973		B.S. Johnson All Bull 195: It was a way of disposing of the dubious intellectuals or the misguided lefties.
1984		‘Derek Raymond’ He Died with His Eyes Open 12: Trendy lefties in and out of politics or just on the edges don’t like us.
1986		R.G. Barrett Godson 366: [L]oonies, lefties and ratbags.
1992		D. Jarman diary 27 June Smiling in Slow Motion (2000) 156: Old lefties squat the march, members of Militant.
2004		C. Brookmyre Be My Enemy 326: How evil and threatening those lefties he spied upon were.
2011		Guardian CIF 8 Aug. 🌐 The people who have been commenting on the riots are righties dressed up as lefties.
2017		T. Spicer Good Girl Stripped Bare 247: ‘You journos, you’re all soft lefties’.