gangster, mobster

a criminal who is a member of gang

• apache — a Parisian gangster
• yardie — member of an international gang of Jamaican criminals who sell drugs and violence
• Capone, Al Capone, Alphonse Capone, Scarface — United States gangster who terrorized Chicago during Prohibition until arrested for tax evasion (1899-1947)

• criminal, felon, crook, outlaw, malefactor — someone who has committed (or been legally convicted of) a crime

• gang, pack, ring, mob — an association of criminals