Green’s Dictionary of Slang

1. pertaining to swindlers and confidence tricksters.

1872		Chicago Trib. 18 Oct. 8/4: A quintet of bunco thieves were tried by jury.
1887		W.T. Call Josh Hayseed in N.Y. 64: I’ve got respect for the bunko chaps.
1893		L. Chittenden ‘A Stockman’s Adventures in New York’ in Ranch Verses 162: Ah, them Bunco Boys iz artful, az all pious men agree.
1902		‘Hugh McHugh’ It’s Up to You 100: Clara J., the Bunco Girl! Did you hear her say, ‘John, do sixes beat fulls?’.
1905		F. Hutchison Philosophy of Johnny the Gent 37: [J]ust let some good bunk guy [...] show him [i.e. a respectable citizen] where he can beat [...] some bucket shop or somethin like that out of a bunch o’ dough, an’ he'll hang a record to his plant to dig up a bankroll.
1909		I.L. Nascher Wretches of Povertyville 218: The bunco schemes requiring a large amount of money to begin with [...] are no longer profitable.
1911		Hawaiian Star (Honolulu) 13 May 18/4: I said to a young man who wanted to go into the bunko business [...] ‘Young man, you’d better do anything else’.
1924		D. Hammett ‘Zigzags of Treachery’ Nightmare Town (2001) 127: He had worked one of his bunko tricks upon me.
1933		(con. late 19C) H. Asbury Barbary Coast 289: Black Tony joined the bunco gang headed by Mike Gallo.
1951		D. Dressler Parole Chief 217: There is always one more person to fall for the wiles of the bunco operator.
1977		D. Powis Signs of Crime 175: Bunco Fraud generally.
1981		J. Wambaugh Glitter Dome (1982) 81: The whole incident was dismissed by bunco detectives as an obvious prank.
2001		(con. 1964–8) J. Ellroy Cold Six Thousand 34: Pete sketched hall routes [...] One bunco pen. One holding tank adjacent.
2007		(con. 1962) E. Bunker Stark 14: He and Dummy had been in prison together. He for a bunko caper that went bad.

2. deceptive, fraudulent.

1903		Ade People You Know 167: He was not such a Hot Swell as he had looked to be in the Bunko Photograph.
1903		A.H. Lewis Boss 165: I’ve been doin’ th’ bunco act so long with our three friends that my face begins to ache with lookin’ pious.
1955		‘Ed Lacy’ Best that Ever Did It (1957) 93: You’ve been giving me a bunko story from the start.
1990		S. Morgan Homeboy 25: She palmed Joe a twenty, his cut of the Murphy, as any bunko prostitution game was called.
1997		H.S. Thompson Proud Highway xix: That Hunter has continued to be called a journalist is one of the great underrated bunco exploits of our age.
2006		F.X. Toole Pound for Pound 157: That way, the bunko punks could collect, and never have to fight.