Green’s Dictionary of Slang

(US) pertaining to Central or South America.

1900		N.Y. Times 20 May 12: Whatever the origin, one hears everywhere of spiggoty people, spiggoty money, and all else spiggoty. Everybody uses the term, the natives having almost accepted it as a proper designation.
1913		H.A. Franck Zone Policeman 88 212: A man who [...] dropped into the waiter’s hand ‘35 cents spig’—which is half as bad as to do it in U.S. currency. [Ibid.] 235: A burly soldier [...] howling some joyful song with six or seven little ‘Spig’ policemen climbing about his frame.
1935		J. Conroy World to Win 39: Leo was small, wiry, dark and alert, like his ‘spiggoty’ mother.
1937		J.M. Cain Serenade (1985) 7: Down there you make it simple, because spig reception isn’t any too good.
1937		J.M. Cain Serenade 190: I told them I could do spig songs in Spanish.
1943		W.R. Burnett Nobody Lives for Ever 106: ‘I think this spig band’s going to play forever.’ ‘This “what” band?’ Jim was puzzled, then he understood. ‘Oh—this South American band, or whatever it is’.