nosedive vs dive

nosedive and dive both are nouns.

Word	Noun	Adjective	Verb	Adverb
nosedive	Yes	No	Yes	No
dive	Yes	No	Yes	No

As nouns, nosedive and dive are synonyms defined as:

Other synonyms of nosedive include nose dive.

As verbs, dive is a hypernym of nosedive; that is, dive is a word with a broader meaning than nosedive:

Other hypernyms of nosedive include plunge, plunk.

nosedive (noun)	dive (noun)
a steep nose-down descent by an aircraft	a steep nose-down descent by an aircraft
a sudden sharp drop or rapid decline	a headlong plunge into water
	a cheap disreputable nightclub or dance hall

nosedive (verb)	dive (verb)
plunge nose first; drop with the nose or front first, of aircraft	drop steeply
	swim under water
	plunge into water