Green’s Dictionary of Slang

1. (US) a young inexperienced man.

1828		High Life in London 27 Jan. 5/2: Oh! Gemini! to see the airs and graces of the stick-twirling bantams, the tossing heads of mincing Mesmoiselles.
1860		Ashtabula Wkly Teleg. (OH) 28 Jan. 1/4: ‘Per-haps, my old cock, you think that’s all the money I’ve got [...] ’ said he [...] ‘Pretty well crowned, my bantam,’ said the latter, as he keenly scrutinized the notes.
1866		Penny Illus. Paper (London) 13 Oct. 10/1: ‘Keep alongside o’ the ring, where I can see yer [...] my little bantam’.
1906		D. Stewart Vultures of the City in Illus. Police News 22 Dec. 12/2: ‘We’ll have some hot coffee, my little bantam’.
1927		B. Cormack Racket Act II: Get in there! You bantam, you got a lot o’ gall, but no brains—like all you young ones.
1938		R. Hyde Nor the Years Condemn 182: We can get all the shawls we want, without this bantam.

2. a lover, a womanizer.

1883		Louisiana Democrat 14 Feb. 1/6: It is time enough for these bantams to think of finding a pullet when they have raised money enough [...] to build a henhouse.
1885		Bulletin (Sydney) 4 Apr. 22/1: The reverend gentleman was very much cut up, indeed, when he heard that his better half had hooked it. The lady […] was very prepossessing, and had many warm admirers. The churchwarden, though, was the favourite bantam.
1928		C. McKay Home to Harlem 307: They were quarreling over a vain black bantam, one of the breed that delight in women’s scratching over them.

3. (Aus.) a person with a hot temper.

1924		G.H. Lawson Dict. of Aus. Words And Terms 🌐 BANTAM—A hot-tempered person.
1955		L. Allen Hot Stove League 151: [A] red-headed bantam from Ashland, Pennsylvania, who spent his boyhood [...] learning to fight during his lunch hour .

4. (US black, also banter) a young woman.

1941		D. Burley N.Y. Amsterdam Star-News 19 July 13: The Chippies and the bantams, the Fillies and the Hens.
1944		D. Burley Orig. Hbk of Harlem Jive 12: [I] rolls it over in my conk that this is a wild banter that’s trying to flop but can’t fly. [Ibid.] 133: Bantam — A young girl, a slender young woman.