Green’s Dictionary of Slang

1. to pay, to donate.

1816		J.H. Lewis Lectures on Art of Writing (1840) 93: He’s forking out the cash.
1821		W.T. Moncrieff Tom and Jerry III ii: tom: She wants the tippery – there – (gives money). There that’s the figure, Jerry! [...] jerry: Oh, I must fork out, too (gives money).
1830		Lytton Paul Clifford III 128: The parson forks him out ten shiners.
1836		Berks. Chron. 30 July 4/5: Bob Davis [...] evinced, by several low bows, his gratitude at not having been compelled to ‘fork out’ the customary five shillings.
1847		Bell’s Life in Sydney 27 Feb. 3/2: My heart rebels / Against all ‘forking out’.
1848		‘Ned Buntline’ Mysteries and Miseries of N.Y. I 111: I never let my clients go there if they fork up handsomely.
1849		Sam Sly 14 Apr. 2/3: W—m Ma——g, of Louisa-street, Mile-end, to mind what he is about with Emma, or he may have half a crown a week to pay [i.e. child support].
1855		Delhi Sketch Bk 1 Jan. 2/2: [A] customer to whom he might say, / ‘A certain sum from your purse you must fork’.
1856		C. Reade It Is Never Too Late to Mend III 222: So now fork out the blunt for the turps.
1869		‘Rights of Women’ in C. Hindley Curiosities of Street Lit. (1871) 82: You must not crib a shilling from your wages on Saturday night, but fork it all out.
1873		‘Cuthbert Bede’ Little Mr. Bouncer 142: If you want me to fork out for anything you’ve got against me, I daresay Stump and Rowley can find the cash.
1877		E.L. Wheeler Deadwood Dick in Beadle’s Half Dime Library I:1 83/1: ‘Durned a cent I’ll fork!’ growled an old fellow.
1885		Bulletin (Sydney) 8 Aug. 6/1: The police, with professional promptitude, headed the procession with grappling-irons. They forked out a billy-goat, and, ever since, when Charles meets an animal of that genus, his features become hard and unforgiving.
1898		W. Pett Ridge Mord Em’ly 288: I thought you wouldn’t fork out nothing.
1908		Sporting Times 15 Feb. 2/5: Blimy, that does take it! I don’t ’ave ter pay to see ’is real royal nibs, but I’m ter fork out ter see these ’ere sham ones.
1915		G. Bronson-Howard God’s Man 15: ‘Fork out. Come on,’ he said, shaking Quivvers. ‘Fork.’.
1916		E. Pound letter 31 Jan. in Read Letters to James Joyce (1968) 68: If the Egoist publish you now, I don’t suppose they’ll be able to make any further advance. Though they might be able to fork up something (I doubt it) later.
1922		Joyce Ulysses 4: We must go to Athens. Will you come if I can get the aunt to fork out twenty quid?
1926		E. Walrond Tropic Death (1972) 122: Yo’ ent gwine get dis goat back to-night till yo’ fork up dat shillin’.
1935		(con. 1920s) J.T. Farrell Judgement Day in Studs Lonigan (1936) 576: Do you think I forked out my initiation fees to be plunked in here all afternoon...?
1936		(con. 1830s–60s) ‘Miles Franklin’ All That Swagger 409: Old Humphrey wants to fly, and will fork-up for that.
1938		F.D. Sharpe Sharpe of the Flying Squad 330: I forked him a quid.
1948		C. Day Lewis Otterbury Incident 65: The old lady forked out a bob.
1953		A. Buckeridge Jennings’ Diary 57: I forked out a large chunk of Matron’s money to pay for it.
1954		A. Buckeridge According to Jennings (1991) 76: We shall have to fork up out of our own pockets.
1960		E. De Roo Big Rumble 118: The dough is forked for the rent.
1974		‘P.B. Yuill’ Hazell Plays Solomon (1976) 121: You’ll start snooping as long as they can fork up the cash.
1977		J. Rosenthal Spend, Spend, Spend Scene 67: Keith also forked out thirty bob a week for a baby called Kim who he reckoned to be the father of.
1989		S. Armitage ‘Bus Talk’ in Zoom 22: He said it would have to look / like the Brighton bombing before they’d even think / of forking out.
1994		G. Disher Crosskill [ebook] ‘[W]e fork out ten thousand dollars and he gets away with it’.
1999		Indep. Rev. 4 Aug. 5: If we refuse to fork out £101 towards making it what it is, we end up in court.
2000		Guardian Sport 1 Apr. 12: I is in the position of the rest of the punters of this world and is obliged to fork out for me OK to research important facts.
2001		(con. 1964–8) J. Ellroy Cold Six Thousand 534: You owe the Golden Caven eleven-sixty. Fork up or Brother Liston will hurt you.
2008		Sun. Times (S.Afr.) 6 Jan. 1: Mr Moneybags: Schabir Shaik forked out for all Zuma’s needs.
2014		T. Black Artefacts of the Dead [ebook] A bad speed bump or a clipped kerb and he’d be forking out for a new one.

2. other than money, to hand over.

1835		G. Kent Modern Flash Dict. 14: Fork it out – to produce any thing by the hand.
1848		Flash Dict. in Sinks of London Laid Open [as cit. 1835].
c.1850		Duncombe New and Improved Flash Dict.
1866		J. Greenwood Night in a Workhouse 20: ‘Whereabouts is it?’ I ses. ‘In that box under my bed,’ he ses, and he forks it out.
1871		Hamilton Spectator (Vic.) 7 Jan. 1/7: But if he [i.e. a father] won't ‘prove game,’ and ‘fork out,’ then I am afraid ‘it’s no go,’ and he [i.e. an indebted son] must ‘skedaddle’.
1898		E. Pugh Tony Drum 49: ‘Fork it out, Funny-Face!’ commanded Honor. [...] He hastily dropped the mouth-organ at her feet, and fled.