defending vs athletics

defending is not a noun while athletics is a noun.

Word	Noun	Adjective	Verb	Adverb
defending	No	Yes	No	No
athletics	Yes	No	No	No

defending (noun)	athletics (noun)
	an active diversion requiring physical exertion and competition
	participation in sports events as an extracurricular activity
	a contest between athletes

defending (adjective)	athletics (adjective)
attempting to or designed to prevent an opponent from winning or scoring