sex vs rub

sex and rub both are nouns.

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

sex (noun)	rub (noun)
activities associated with sexual intercourse	the act of rubbing or wiping
the properties that distinguish organisms on the basis of their reproductive roles	an unforeseen obstacle
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

sex (verb)	rub (verb)
tell the sex (of young chickens)	move over something with pressure
to evoke sexual feelings	cause friction
	scrape or rub as if to relieve itching