sex vs working girl

sex and working girl both are nouns.

Word	Noun	Adjective	Verb	Adverb
sex	Yes	No	Yes	No
working girl	Yes	No	No	No

sex (noun)	working girl (noun)
activities associated with sexual intercourse	a young woman who is employed
the properties that distinguish organisms on the basis of their reproductive roles	a woman who engages in sexual intercourse for money
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)	working girl (verb)
tell the sex (of young chickens)
to evoke sexual feelings