newspaper ad vs advert

newspaper ad and advert both are nouns.

Word	Noun	Adjective	Verb	Adverb
newspaper ad	Yes	No	No	No
advert	Yes	No	Yes	No

As nouns, advert is a hypernym of newspaper ad; that is, advert is a word with a broader meaning than newspaper ad:

Other hypernyms of newspaper ad include ad, advertisement, advertising, advertizement, advertizing.

newspaper ad (noun)	advert (noun)
a printed advertisement that is published in a newspaper	a public promotion of some product or service

newspaper ad (verb)	advert (verb)
	make a more or less disguised reference to
	make reference to
	give heed (to)