Gangster

n. one who belongs to a gang of criminals

Gangster is the term for a career criminal who is, or at some point almost invariably becomes, a member of a persistent violent crime organization, such as a gang. As an adjective it can be used as an unflattering depiction of the violent and devious methods commonly used by mobsters, and the derived form gangsterism it implies such methods as practice or habit. The term gangster is most commonly used in reference to members of the criminal organizations associated with the American offshoot of the Cosa Nostra and the American prohibition, such as the Chicago Outfit and the Five Families, and individuals such as Al Capone and Bugsy Siegel.
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Noun
1. a criminal who is a member of gang
(synonym) mobster
(hypernym) criminal, felon, crook, outlaw, malefactor
(hyponym) apache
(member-holonym) gang, pack, ring, mob

n. gangster, mobster, one who belongs to a gang of criminals

n. gangster, hijacker