Definition of "Tough" :
noun: a cruel and brutal fellow
noun: an aggressive and violent young criminal
noun: someone who learned to fight in the streets rather than being formally trained in the sport of boxing
adjective: feeling physical discomfort or pain (tough' is occasionally used colloquially for bad')
"He was feeling tough after a restless night."
adjective: substantially made or constructed
"A tough all-weather fabric."
adjective: making great mental demands; hard to comprehend or solve or believe
adjective: very difficult; severely testing stamina or resolution
"The competition was tough."
adjective: unfortunate or hard to bear
"A tough break."
adjective: resistant to cutting or chewing
adjective: physically toughened
"The tough bottoms of his feet."
adjective: not given to gentleness or sentimentality
"A tough character."
adjective: violent and lawless
"Tough street gangs."