Green’s Dictionary of Slang

1. money as used in any form of contract.

1812		Vaux Vocab. of the Flash Lang. in McLachlan (1964) 274: The tip is a term frequently used to signify the money concerned in any dealings or contract existing between parties; synonymous with the dues.
1821		‘An Amateur’ Real Life in London I 145: I knows very well as how he’s got the tip in his pocket.
1830		Egan Finish to the Adventures of Tom and Jerry (1889) 119: All I looks after is the tip – and to prevent bolters.
1833		‘Flare Up!’ in Rake’s Budget in Spedding & Watt (eds) Bawdy Songbooks (2011) III 66: Eere they commenc’d — to stash all frauds, / She wanted tip.
1848		Flash Dict. in Sinks of London Laid Open.
1861		(con. 1840s–50s) H. Mayhew London Labour and London Poor I 425/1: The party of the house produces the bill, which promises a stunning tip for the old lumber.
1870		Hotten Sl. Dict.
1880		E.J. Milliken ‘Cad’s Calendar’ in Punch Almanack n.p.: The Boss will drop a tip, – ’ope so, at least.

2. money.

1866

Letters by an Odd Boy 101: ‘Look here, got any tip?’ ‘Tip?’ ‘Ugh! yer six days old! Eyes not open yet, eh! — blunt, stumpy, coppers — a joey — a tanner — a bob — money, yer muff’.

3. a bribe.

1812		Vaux Vocab. of the Flash Lang. in McLachlan (1964) 274: tip: to give, pay, or bribe. To take the tip, is to receive a bribe in any shape; and they say of a person who is known to be corruptible, that he will stand the tip.
1852		Bathurst Free Press (NSW) 21 Apr. 2/2: Now the slang phraseology of New South Wales contains such a word as ‘tip,’ the elegant! English of which is ‘bribery’.
1882		Nat. Police Gaz. (NY) 18 Mar. 2/1: [I]n sporting events, all the fellows who have taken ‘tips’ have been turned over.