A confidence game or swindle, or a form of dice gambling; also spelled 'bunko,' often used in the phrase 'bunco squad' for police who investigate fraud.
From Spanish 'banca' (bank) or possibly from Sicilian 'banco,' this term entered English in the 1870s-1880s describing fraudulent games and schemes.
The word bunco became so famous for scams that police units fighting fraud were actually called 'Bunco Squads'—it was basically the 19th-century version of the FBI's fraud division!
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