Green’s Dictionary of Slang

(US) to place a bet.

1896		H. Blossom Checkers 43: One day a tout tried to ‘get me down’ on a ‘good thing’ he had.
1908		B. Fisher A. Mutt in Blackbeard Compilation (1977) 78: Cicero has gone to Schinassi’s poolroom to get down a few piasters for me.
1912		C. Mathewson Pitching in a Pinch 174: ‘Bill’s’ horse walked home, and he could not get a bet down on him.
1921		R. Lardner ‘A Frame-Up’ in Coll. Short Stories (1941) 434: I and Jack did get down a couple of bets, fifty apiece.
1941		A. Lomax Mister Jelly Roll (1952) 115: So I told the boys, ‘All right, get down on this card.’ ‘Getting down’ means to put some money up.
1951		W. Winchell On Broadway 2 Mar. [synd. col.] Basketball ‘fixer’ Sollazzo [...] could only ‘get down’ with mid-western outfits.
1957		C. Himes Imabelle 23: The bettors got down, win and lose, in the books.
1965		C. Himes Rage in Harlem (1969) 23: [as 1957].
1972		(con. 1950s) D. Goines Whoreson 104: I realized that very few of the so-called ‘hustlers’ really knew how to get down.
1981		J. Wambaugh Glitter Dome (1982) 191: He got a little action down maybe once, twice, is all. He talks like some kinda player, but he never spent more than a hundred bucks with me.
2011		G. Hayward Corruption Officer [ebk] cap. 1: Get down, nigga. I know you ain’t come here to sightsee!