gangster (n.)

• bandit
• betrayer
• brigand
• convict
• criminal
• crook
• dacoit
• deceiver
• delinquent
• desperado
• double-dealer
• evildoer
• felon
• fugitive
• gaolbird
• goon
• gunman
• gunslinger
• hood
• hoodlum
• hooligan
• jailbird
• lawbreaker
• malefactor
• malfeasant
• mobster
• mugger
• outlaw
• quisling
• racketeer
• robber
• ruffian
• scofflaw
• sinner
• skinhead
• soldier
• swindler
• thief
• thug
• torpedo
• tough
• traitor
• transgressor
• two-timer
• villain
• wrongdoer