arena vs area

arena and area both are nouns.

Word	Noun	Adjective	Verb	Adverb
arena	Yes	No	No	No
area	Yes	No	No	No

As nouns, area is a hypernym of arena; that is, area is a word with a broader meaning than arena:

arena: the central area of an ancient Roman amphitheater where contests and spectacles were held; especially an area that was strewn with sand
area: a particular geographical region of indefinite boundary (usually serving some special purpose or distinguished by its people or culture or geography)

Other hypernyms of arena include country.

As nouns, arena and area are synonyms defined as:

Other synonyms of arena include domain, field, orbit, sphere.

arena (noun)	area (noun)
a playing field where sports events take place	a part of a structure having some specific characteristic or function
a large structure for open-air sports or entertainments	the extent of a 2-dimensional surface enclosed within a boundary
the central area of an ancient Roman amphitheater where contests and spectacles were held; especially an area that was strewn with sand	a part of an animal that has a special function or is supplied by a given artery or nerve
a particular environment or walk of life	a subject of study
	a particular geographical region of indefinite boundary (usually serving some special purpose or distinguished by its people or culture or geography)
	a particular environment or walk of life