Cosa Nostra refers to a term signifying organized crime, and one of a variety of names for the mafia, the mob, etc. Literally, it means 'our thing'
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Cosa Nostra is a term which literally means "our thing" and refers to or signifies organized crime, and one of a variety of names for the "Mafia," the "Outfit," the "Mob," the "syndicate," or "the organization."