sex vs crotch

sex and crotch both are nouns.

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

sex (noun)	crotch (noun)
activities associated with sexual intercourse	the angle formed by the inner sides of the legs where they join the human trunk
the properties that distinguish organisms on the basis of their reproductive roles	external sex organ
all of the feelings resulting from the urge to gratify sexual impulses	the region of the angle formed by the junction of two branches
either of the two categories (male or female) into which most organisms are divided

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