Possible Definitions:
1. Arena (n.) The area in the central part of an amphitheater, in which the gladiators fought and other shows were exhibited; -- so called because it was covered with sand.
2. Arena (n.) Any place of public contest or exertion; any sphere of action; as, the arenaof debate; the arena of life.
3. Arena (n.) "Sand" or "gravel" in the kidneys.
