Arena

n.	1.	(Rom. Antiq.) 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.	Any place of public contest or exertion; any sphere of action; as, the arenaof debate; the arena of life.
	3.	(Med.) "Sand" or "gravel" in the kidneys.

Noun	1.	arena - 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" Synonyms: domain, sphere, area, orbit, field
	2.	arena - the central area of an ancient Roman amphitheater where contests and spectacles were held; especially a sand-strewn area
	3.	arena - a large structure for open-air sports or entertainments Synonyms: sports stadium, stadium, bowl
	4.	arena - a playing field where sports events take place Synonyms: scene of action

(programming)

arena - The area of memory attached to a Unix process by the brk and sbrk system calls and used by malloc as dynamic storage. So named from a "malloc: corrupt arena" message emitted when some early versions detected an impossible value in the free block list. See overrun screw, aliasing bug, memory leak, memory smash, smash the stack.

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