Green’s Dictionary of Slang

cinch n.1

also sinch, skinch
[SE cinch, to grip tightly; thus something one can grasp easily. Orig. f. Sp. cincha, a saddle girth or bellyband, adopted in US Western use]

1. (US) a fool, one who can be easily overcome [ext. of sense 2].

[US]S. Crane in N.Y. Press 9 Dec. in Stallman (1966) 113: Say, if yeh pick me up fer a cinch, I’ll fool yeh.
[US]Boston Globe Sun. Mag. 21 Dec. 7–8: A professor who is at all lenient in his methods of instruction is a ‘cinch’.
[US]Eve. Star (Wash., DC) 29 July 34/1: I’m a cinch [...] Every panhandler [...] knows he can work me for a beer check.
D. Runyon ‘A Tale of two Fists’ XV in Pittsburgh Press (PA) 16 May 31/1: ‘I used to be cinch for any one to pop on the chin’.

2. (orig. US, also kinch, sinkers) a simple, easily attained thing, a certainty; thus cinchy, sinchy, easy, easily attained or attainable; cinch-looking, apparently easy.

[US]Lantern (N.O.) 5 Mar. 3: Rube claims to be a tout, and gets around the greenies saying he has a sinch but if he ain’t careful, he’ll bite the dust.
[US]E. Townsend Chimmie Fadden Explains 25: I mean dose pieces what says what mug has de dead cinch on bein de dandiest dresser on de avenoo.
[US]C.L. Cullen Tales of the Ex-Tanks 223: The cinch-looking price of 3 to 5 or 1 to 2.
[US]‘Hugh McHugh’ Down the Line 16: ‘A skinch!’ said Nash. ‘Go as far as you like.’.
[US]A.H. Lewis Boss 96: He grafts nights [...] an’ at this time of day it’s a cinch he’s takin’ a snooze.
A. Kleberg Slang Fables from Afar 12: [T]the winning of the hearts of the Kroywen Fancy Work was Sinchy for Browne.
[US]St Paul Globe (MN) 7 Aug. 27/2: It’s sinkers fer de bunch dat Romeo and his bundle is up de pike in a minute on the merry get-away.
[Aus]Sun. Times (Perth) 1 July 4/7: From him to sneak to a job with Leake / Was a ‘kinch’ to my acrobat organs.
[US]H.G. van Campen ‘Our Theatrical Boarding House’ in L.A. Herald 10 Dec. 10/4: ‘Don’t yuh never git the notion bein’ a mechanic’s a cinch, sister‘.
[US]M. Glass Potash and Perlmutter 1: This brokering business ain’t such a cinch neither.
[UK]Wodehouse Carry on, Jeeves 35: ‘It’s a cert!’ I said. ‘An absolute cinch!’ said Corky.
[US]W.R. Burnett Little Caesar 37: This ain’t going to be no cinch.
[US]Ade Old-Time Saloon 138: The syndicate [...] appeared to be making a safe bet, because [...] it seemed certain that the profits would continue and the dividends would be a cinch.
[Aus]Truth (Brisbane) 2 Feb. 42/1: ‘It’s a cinch, you'd have been late for breaker’.
[UK]J. Curtis You’re in the Racket, Too 61: It’s a cinch, we’ll have it off sweet as a nut.
[US]Mezzrow & Wolfe Really the Blues 53: Why didn’t I ask my sister Helen to take down the words in shorthand? She was doing secretarial work and [...] it would be a cinch for her.
[US]Kramer & Karr Teen-Age Gangs 9: Cinch handled a few stick-ups and was, as he said, a cinch at stealing cars.
[US]‘Iceberg Slim’ Mama Black Widow 71: It’s a cinch I ain’t gonna’ burn my own baby brother.
[UK]P. Theroux Picture Palace 43: It is not the cinch it seems for a photographer to take her own picture.
[US]C. Hiaasen Skin Tight 40: A cinch [...] We can do it under local anesthetic, make it smooth as silk.
[US]E. Bunker Mr Blue 215: Within the month he was going to court for sentence and it was a cinch he was going where I had just been.
[UK]Guardian Editor 25 June 16: It’s a cinch. You just chuck the eggs and flour together and knead for glory.

3. (US) an easily seduced woman.

[US]J.L. Kuethe ‘Johns Hopkins Jargon’ in AS VII:5 330: cinch—[...] a woman who is easily possessed.

In phrases

have the cinch on (v.)

to place oneself in an unassailable position.

[US]Kansas Agitator (Garnett, KS) 21 July 5/1: The coal men feel confident that they have a cinch on the trade.
[US]C.L. Cullen Tales of the Ex-Tanks 105: We were going to get those railroad tickets [...] so that we’d have a cinch on going back East.
[US]J. London Road 24: The tramp, snugly ensconced inside the truck, with the four wheels and all the framework around him, has the ‘cinch’ on the crew — or so he thinks.
[US]Day Book (Chicago) 22 Sept. 28/1: Private capital will have a cinch on charging us all high prices for our dyed textiles.
[US](con. 1918) J. Stevens Mattock 273: Dill wants to get a sure cinch on Johnny Hard, and have him busted.
put the cinch on (v.)

(US) to ensure, to make something certain.

[US]L.A. Herald 27 Mar. 5/5: In the ninth inning San Jose put a cinch on their victory by getting two runs.
[US]Austin’s Hawaiian Wkly (Honolulu, HI) 18 Nov. n.p.: The Supreme Court has put a tighter cinch on the meaning of the ‘opinion in possession’ clause of the law.
[UK]C. Holme Lonely Plough (1931) 108: I had him wobbling, as it was. You can put the cinch on him, if you choose.
[US]‘Iceberg Slim’ Pimp 44: He had [...] pulled strings, and put the cinch on the joint for me.