Arena

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.

Any place of public contest or exertion; any sphere of action; as, the arenaof debate; the arena of life.

"Sand" or "gravel" in the kidneys.

a large structure for open-air sports or entertainments

a particular environment or walk of life; "his social sphere is limited"; "it was a closed area of employment"; "he's out of my orbit"