dive vs nose dive

dive and nose dive both are nouns.

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

As nouns, dive and nose dive are synonyms defined as:

Other synonyms of dive include nosedive.

dive (noun)	nose dive (noun)
a steep nose-down descent by an aircraft	a steep nose-down descent by an aircraft
a headlong plunge into water
a cheap disreputable nightclub or dance hall