Able to withstand great strain without tearing or breaking; strong and resilient, Strong-minded; resolute, Inclined to violent or disruptive behavior; rowdy or rough, noun_ A person who obtains things by force; a thug or bully, To toughen, someone who learned to fight in the streets rather than being formally trained in the sport of boxing, verb_ To endure, To toughen
A referee, (sports) the chief official (as in boxing or American football) who is expected to ensure fair play, Short form of referee, verb_ informal to referee; to act as a referee in a sport or game, abbreviation_ reference, refectory