Green’s Dictionary of Slang

bouncy adj.

1. (US) voluptuous.

1953

E. Wilson Look Who’s Abroad Now 22: When Marilyn [Monroe] joined us [...] she looked extremely bouncy in a low-cut dress.

2. (US prison) physically aggressive.

1963

in T.I. Rubin Sweet Daddy 37: Some of these civil service creeps [i.e. warders] got big ideas. Get a little bouncy once in a while. Bouncy. Beat up a con.

SE in slang uses

In compounds

In phrases

bouncy in one’s brace of dukes [lit. bouncing up and down on one’s legs, ‘bowing and scraping’]

(US black) subservient to white people.

1944

D. Burley Orig. Hbk of Harlem Jive 19: He ain’t never had to get bouncy in his brace of dukes.