annunciate vs harbinger

annunciate is not a noun while harbinger is a noun.

Word	Noun	Adjective	Verb	Adverb
annunciate	No	No	Yes	No
harbinger	Yes	No	Yes	No

As verbs, annunciate and harbinger are synonyms defined as:

Other synonyms of annunciate include announce, foretell, herald.

annunciate (noun)	harbinger (noun)
	something that precedes and indicates the approach of something or someone

annunciate (verb)	harbinger (verb)
foreshadow or presage	foreshadow or presage