Green’s Dictionary of Slang

guinea n.1

[18C guinea, a black. The original guineas were black slaves from the Guinea Coast of Africa, and the term gradually evolved to mean anyone with a notably dark complexion, although it is rarely if ever used to describe a black person in 20C+ other than in the SE Guinea Negro, a mixed-race group native to Maryland, Virginia and West Virginia, who call themselves Our People or Melungeons]
(US)

1. (also ghini, ghinny, gin, ginee, ginney, ginny, guin, guiney, guinney, guinny, guiny, guinzo, guinzola) an Italian person, usu. an immigrant to the US.

[US]N.Y. Daily Trib. 17 July 8/1: The ‘Hoodlum’ of New-York, with his senses deadened to the beauty of the Latin tongue and the mellow Neapolitan accent, has bestowed upon the races that use it with such volubility the names of ‘Guineas’ and ‘Dagoes.’.
[Aus]Dead Bird (Sydney) 31 Aug. 2/2: Characters: Australianised Italian and fresh cop. Cop: [...] Anything happened round here to-night, Ginny?
[US]Harper’s Weekly 16 Oct. 817: The lower ‘sporting’ elements in the poorer quarter of New York call them ‘Guineas’ and ‘Dagoes’.
[US]E. Townsend Chimmie Fadden Explains 203: She come up here from Cherry Hill and took up with a Guinny here in Mulberry Bend. [...] Some of the Italian men scowled at the word ‘Guinny’.
[US]E. Townsend Chimmie Fadden and Mr Paul 40: Naples, a guinney district where de street-sweepers come from.
[US]J.A. Riis Battle with the Slum 314: Complaint had been made that there were too many ‘Ginnies’ in the Gio flat.
[US]M. Kelly Little Citizens 204: I know where we can hook a banana. And the Ginney’s asleep.
[US]‘O. Henry’ ‘The Coming-Out of Maggie’ in Four Million (1915) 80: I knew he was a Guinea. His name’s Tony Spinelli.
[US]G. Bronson-Howard God’s Man 147: If I’d been born a Hunky or a Ginny, or even a Yiddisher boy – but Irish – ! – !
[UK]E. Poole Harbor (1919) 314: I am an Italian man! You call me Guinney, Dago, Wop.
[US]J. Lait ‘Canada Kid’ in Beef, Iron and Wine 1917 172: Well, whaddaye know about dat dere stingy Guinea, huh?
[US]E. O’Neill Hairy Ape 25: De Black Hand, dey’re a lot of yellow backstickin’ Ginees.
[US]G.H. Mullin Adventures of a Scholar Tramp 125: Guineas! The bunk-car stunk.
[US]C. Coe Hooch! 243: That little ginney over there.
[US]D. Runyon ‘Gentlemen, the King!’ in Runyon on Broadway (1954) 180: A bomb such as these Guineas like to chuck at people they don’t like.
[US]J.T. Farrell Gas-House McGinty 56: Still living out there in Cicero with the Ginnies and foreigners, huh, Willie?
[US]E. Anderson Hungry Men 90: You go to hell, you goddamned guiney.
[US]J. Weidman I Can Get It For You Wholesale 291: ‘Try to remember my face is covered with skin,’ I told the ginney, ‘not asphalt.’.
[US]E. O’Neill Iceman Cometh Act I: Jees, I’ll bet he’d give yuh an awful beatin’, [...] Ginnies got awful tempers. [Ibid.] Act II: A dirty little Ginny pimp, dat’s what!
[US]E. Pyle Here Is Your War (1945) 182: All men in the outfit were instructed to refer to Italians as ‘Guineas’.
[US]Goldin et al. DAUL 81/1: Ginney. An Italian [...] Ginzola. (also Ginzo). A ginney. [Ibid.] 87/2: Guin [...] Guinea. Guinzola. (also Guinzo). An Italian.
[US]J. Jones From Here to Eternity (1998) 567: Wops, and Spiks, and [...] Guinies, and Niggers, no got the heart.
[US]B. Schulberg On the Waterfront (1964) 119: The Irish and Italians — the Micks and the Guineas.
[US]Ragen & Finston World’s Toughest Prison 801: ginny – An Italian.
[US]H. Selby Jr Last Exit to Brooklyn (1966) 48: I’ll wait until after that big-cocked guinea has fucked me.
[US]M. Puzo Godfather 240: He was a big man [...] Not the usual greasy dark guinzo husband but crew-cut blond. [Ibid.] 240: She was getting dressed up in the real New York City guinzo style.
[US]E. Tidyman Shaft 114: All you got to do is put yourself in some crazy guinea’s head.
[US](con. 1960s) R. Price Wanderers 10: Wanderers (ginny) 27 Pharoahs (ginny) 28 Rays (irish).
[US]R. Price Blood Brothers 230: Them guinzos is thick as thieves.
[US](con. 1949) J.G. Dunne True Confessions (1979) 28: Here was one ginney getting his glass blown [...] and another ginney comes in and gives him three in the pump.
[US]J. Sayles Union Dues (1978) 26: Stupid fuckin ghinny.
[US]R. Price Breaks 61: Three P.R.’s and a disco Ginny.
[US]M. La Sorte La Merica (2003) 138: an Italian was not an Italian. He was a wop, dago, duke, gin, tally, ghini, macaroni or spaghetti or spaghetti bender. He was also Hey Boy or Hey Youse, or he was given a generic name: Joe, Pete, Tony, Carlo, Dino, Gumba.
[US](con. 1970s) J. Pistone Donnie Brasco (2006) 322: ‘A fucking New York guinea, aren’t you?’ ‘Well, I am from New York and I am Italian.’.
[UK]T. Fontana and S. Jablonski ‘Ancient Tribes’ Oz ser. 2 ep. 2 [TV script] Scibetta? Why you giving that guinea my job?
[US] ‘Sally Forth’ [comic strip] ‘You’re like a guinea pig in my experiment.’ ‘Say! That’s not very nice! Besides, I’m not even Italian!’.
[US](con. 1973) C. Stella Johnny Porno 28: I had half a dozen guys as tough as you I’d be one happy guinea.
[US]D. Winslow The Force [ebook] The slick guinea has saved Malone’s life more times than he can count.

2. a derog. term for various other non-Anglo nationalities, usu. Mediterranean, e.g. a Greek, a Portuguese, a Jew.

[UK] ‘Plunder Creek’ in Bentley’s Misc. Feb. 127: [to a negro] You tarnation Guinea-crow.
[US]Jackson & Hellyer Vocab. Criminal Sl. 39: guinea [...] Europeans generally.
see sense 1.
[US]I. Wolfert Tucker’s People (1944) 8: It had said in the paper Leo’s brother was ‘Guinea Joe’ Minch.

3. (US Und.) a woman.

[US]F.H. Tillotson How I Became a Detective 88: A ‘guinea’ or ‘Bowser’ is a woman.

4. (also ginney) a foolish, gullible or insignificant man.

[US]Jackson & Hellyer Vocab. Criminal Sl. 39: guinea [...] In the sense of a man it is synonymous with ‘gazab’ ‘gink,’ ‘mark’.
[US]C.B. Booth ‘Mr Clacksworthy Within the Law’ Detective Story 13 Aug. [Internet] You ain’t tryin’ to tell me that a wise guinea like old Denton is handin’ out any fifty-thousand-dollar checks.
[US]A.J. Pollock Und. Speaks 45/2: Ginney, a no-account man; a moron.
[US]Baker et al. CUSS 131: Guinea A small or insignificant person.
[US]H. Gould Fort Apache, The Bronx 77: Guys who beat up the wrong guinea.

5. a Japanese person, a Pacific native.

[US]D.W. Hamilton ‘Pacific War Lang.’ in AS XXII:1 Feb. 55: guineas. Same as gooks.

6. (also ginny) a groom in a horseracing stable [US grooms were often of Italian immigrant origins].

[Can] in Lethbridge Herald (Alberta) 22 Mar. 14/4: A groom is a ginny or a swipe.

7. the Italian language.

[US]A. Kahn Brownstone 78: An American’s out of place. Jew talk and guinea, that’s all you hear at the yard.
[US](con. 1960s) R. Price Wanderers 150: Boo-Boo [...] gave Perry crossed forearms, guinea for fuck you.

In phrases

get someone’s guinea up (v.)

to make someone angry.

[US]J. Lait Put on the Spot 39: Now they manhandle Annie an’ toss her in the clink. It gets my Guinea up.