2. In ancient Rome, a professional fighter who fought another combatant, or a wild animal, in public entertainments which took place in an arena.
Often gladiators were criminals, or slaves, who were equipped with nets, nooses, swords, or other weapons for battle to entertain Romans in the circuses.
Soldiers of the sand (arena), who performed for an audience as entertainment. Inherited from the Etruscans, the gladiator performed throughout Italy, including Rome.
Whether military deserters, condemned criminals, slaves, or freemen; in all cases, they were thought to be volunteers because, otherwise, they probably wouldn't be worth the expense of training in the special schools (ludi).
The gladiator could be a very profitable investment and many of them became very wealthy and were as popular as professional athletes are today.