Green’s Dictionary of Slang

1. to give or get an advance on wages, a loan.

1873		Sl. Dict. 314: Sub to draw money in advance; a term in use among workmen generally, and those with casual employment in particular. Most likely from subsidize.
1888		S.O. Addy Sheffield Gloss. 244: Sub, to receive or borrow money on account, to get money in advance of wages or on account of work in progress.
1891		Pall Mall Gazette 19 Nov. 612: During the month there has been a more than usual amount of ‘subbing’ .
1900		N&Q Ser. 9 VI 354/1: ‘I want you to go at once to London.’ [...] ‘All right; but I shall want to be subbed.’.
1936		W.A. Gape Half a Million Tramps 184: In order to carry on they would have to ‘sub’ out of their next week’s wages.
1950		S. Murphy Stone Mad (1966) 97: It reminds me of the time I tried to sub the boss for the loan of a few pounds.
1962		F. Norman Guntz 12: I could always sub a few bob off the governor.
1976		T. Murphy Sanctuary Lamp in Plays: 3 (1994) I ii: We’ll buy a pan – if the Monsignor thinks to sub me.
1981		A. Payne ‘You Need Hands’ in Minder [TV script] 30: Maybe Arthur’ll sub us enough to get the Capri on the road.
1993		I. Welsh Trainspotting 317: Sub us then mate. Ah’m expectin a rent cheque.
2005		B. Hare Urban Grimshaw 236: He had nothing himself, so he couldn’t be expected to sub Urban and me.
2023		M. Herron Secret Hours 216: ‘[I]f you could sub me for a couple of nights? I just need to get my ducks in a row’.

2. to hand over money (e.g., as a bet).

1908		Sporting Times 25 Apr. 4/3: If the outlook is gritty, you’ll go to the City, / And ‘sub.’ a stray quid or a brace; / Then, as soon as you cop ’em, on Land League you’ll pop ’em, / The ‘City and Sub.,’ win and place.
1915		S. Ford Shorty McCabe on the Job 36: He sure is a misfit to be subbin’ on a deeds-of-kindness job.
1955		B. Hill Boss of Britain’s Underworld 122: I had been subbing a family or two round the manor [...] dead straight people who just didn’t know how to earn a crust.

3. to hand over money as a bribe.

1960

C. MacInnes Mr Love and Justice (1964) 136: It is just possible she’s subbing somebody – somebody in the Force, I mean – and getting protection.