sexual activity vs napkin

sexual activity and napkin both are nouns.

Word	Noun	Adjective	Verb	Adverb
sexual activity	Yes	No	No	No
napkin	Yes	No	No	No

sexual activity (noun)	napkin (noun)
activities associated with sexual intercourse	a small piece of table linen that is used to wipe the mouth and to cover the lap in order to protect clothing
	garment consisting of a folded cloth drawn up between the legs and fastened at the waist; worn by infants to catch excrement