Green’s Dictionary of Slang

1. (orig. US Und.) a share, usu. in the spoils of a robbery; a commission on a deal.

1885		Bulletin (Sydney) 11 Apr. 18/4: They are not liable to ‘corners’ and ‘rings,’ and the holders don’t care a snuff for all the ‘Boss Tweeds’ and ‘Jay Goulds’ in creation.
1891		Sporting Times 10 Jan. 3/2: Old Bob [...] must ’ave his corner out of it [i.e. a profitable swindle].
1898		Binstead & Wells A Pink ’Un and a Pelican 118: They would not employ ordinary commission-agents, who would have ‘wanted their corner’ and spoilt the whole thing.
1905		Sporting Times 4 Feb. 1/3: The cost was £100,000, and, needless to say, the contract was given to a general. His ‘corner,’ it transpires, was £20,000.
1925		E. Jervis 25 Years in Six Prisons 69: They are usually quite ready to assist [...] and ‘take their corner’ – that is, get their share – later on.
1930		(con. 1910s) D. Mackenzie Hell’s Kitchen 84: Millie frequently took her ‘corner’ (share) in the gamble.
1932		Sun. Mail (Brisbane) 13 Nov. 20/8: The respectable citizen might hear somebody arguing belligerently with a companion for his ‘corner,’ i.e., his share of the proceeds, and complaining bitterly that the other was trying to ‘put him on the blue,’ in other words, give him nothing.
1938		G. Kersh Night and the City 9: He lived almost entirely on percentages, commissions, corners, rake-offs.
1941		V. Davis Phenomena in Crime 79: At a later date she will receive her ‘corner’.
1950		S.J. Baker in Sun. Herald (Sydney) 8 June 9/4: ‘Corner’ or ‘sling’ means a share in a haul; and ‘not a droob’ means nothing at all.
1963		(con. 1944) L. Glassop Rats in New Guinea 50: We pinned the Eyeties’ ears back an’ the Jerries’ [...] We’ll soon give them blasted Nips somethin’ for their corner, too.
1989		J. Morton Lowspeak.

2. (US black) the last mouthful of a bottle of liquor.

1967		M. Brookins ‘Aspiration’ in Kochman Rappin’ and Stylin’ Out (1972) 381: Having the jug in hand and clearly in the sight of Willie, I expected the first four words out of his mouth to be ‘Save me the corner’.
1969		C. Brown Mr Jive-Ass Nigger 27: Gimme a drink, Reb said. Give you shit, nigger, George said, and took a swig big enough to finish it, but there was still a corner left, so he hand it over to Reb.
1972		O. Hawkins Ghetto Sketches 231: [of a bottle of liquor] ‘You want this corner, chu-man?’ [...] ‘Naw . . . go ’head, y’all kill it.’.
1985		T.R. Houser Central Sl. 16: corner A small portion of the remaining alcoholic beverage [...] which fills the ‘corner’ of the bottle when tipped. ‘Here’s the bottle nigger, just take a corner.’.