Green’s Dictionary of Slang

1. a set of three numbers forming a bet in ‘policy’ or ‘numbers’ gambling.

1841		Flash (NY) 24 Oct. n.p.: The poor woman learned that the ticket was a gig and worth $50.
1845		Nat. Police Gaz. (NY) 16 Oct. 54/2: More recent efforts of genius in the science of policies [i.e. numbers, the n. (1)] have invented ‘horses,’ ‘gigs,’ ‘whips’ and ‘saddles’ [...] those being fancy combinations.
1871		Brooklyn Dly Eagle (NY) 9 Feb. 2/6: Many a person there is who never sees certain numbers under certain circumstances, but what he buys a little policy ‘gig’ to test his luck.
1872		Galaxy (N.Y.) Apr. 494: A ‘flat gig’ is three numbers played for all three to be drawn, and gets its name, I presume, from the fact that it is played by nobody but fools, who are known in the dialect of detectives and thieves as ‘flats’.
1881		Nat. Police Gaz. (NY) 5 Nov. 7/3: Jack Shaw is a noted Bowery player, and ‘Shaw’s gig’ is known from the Battery to Harlem. The numbers composing it are 6, 12, 24, 53 [sic].
1890		Congressional Record 16 Aug. 8713/2: The ‘washerwoman’s gig’ — 4-11-14 — [is] the chance that these three, or any other three numbers, will, in any order, be the first three numbers out of the thirteen taken from the wheel [DA].
1910		S.P. Wilson Chicago Cess-pools of Infamy 158: Three numbers make a ‘gig’ and win $150 to $225 [DA].
1919		O.R. Cohen ‘Pool and Ginuwine’ in Polished Ebony 47: His favourite lottery gigs remained in the big glass wheel.
1928		Yodelling Kid Brown ‘Policy Blues’ 🎵 Well I dreamed last night my gig out.
1938		H. Asbury Sucker’s Progress 92: Gig — Three numbers, to appear anywhere on the list. Odds, 200 to 1. The gig was always the favourite bet of the Negroes, and the most popular of all was 4-11-44, known as the ‘magic gig’ and the ‘Washwoman’s gig’.
1946		Drake & Cayton Black Metropolis 477: Do not play too many different gigs. Put all your energy on one set and wait. Do not be impatient and jump from gig to gig.
1958		Hughes & Bontemps Book of Negro Folklore 204: But if I hit this gig, / Ain’t gonna bust these suds no more! / Four, ’leven and forty-four.
1969		‘Iceberg Slim’ Mama Black Widow 68: A dime played on a gig that hits brings eighty-six dollars.

2. by ext., any set of three.

1949

G.G. Carlson ‘Argot of Number Gambling’ in AS XXIV:3 190: The word gig, which to the gambler is a type of play in policy involving three numbers, has in the vernacular of the community become a synonym for the number three.