adult vs sex

adult and sex both are nouns.

Word	Noun	Adjective	Verb	Adverb
adult	Yes	Yes	No	No
sex	Yes	No	Yes	No

adult (noun)	sex (noun)
any mature animal	activities associated with sexual intercourse
a fully developed person from maturity onward	the properties that distinguish organisms on the basis of their reproductive roles
	all of the feelings resulting from the urge to gratify sexual impulses
	either of the two categories (male or female) into which most organisms are divided

adult (adjective)	sex (adjective)
(of animals) fully developed
designed to arouse lust

adult (verb)	sex (verb)
	tell the sex (of young chickens)
	to evoke sexual feelings