tough - noun

someone who learned to fight in the streets rather than being formally trained in the sport of boxing

an aggressive and violent young criminal

a cruel and brutal fellow

tough - adjective

• not given to gentleness or sentimentality
• physically toughened
• resistant to cutting or chewing
• very difficult; severely testing stamina or resolution
• substantially made or constructed
• violent and lawless
• feeling physical discomfort or pain (`tough' is occasionally used colloquially for `bad')
• unfortunate or hard to bear
• making great mental demands; hard to comprehend or solve or believe

tough - thesaurus

bad   baffling   bully   elusive   goon   hard   hood   hoodlum   hooligan   knotty   problematic   problematical   punk   roughneck   rowdy   ruffian   ruffianly   rugged   sturdy   thug   toughened   toughie   yob   yobbo   yobo