Unalike, contrasting, contrapositive, varying, unlike
The word ancient is an adjective. It means very old.
Yes, it is an adjective. The adjective equine means of or about a horse or some very similar animal.
Antsy is in fact an adjective. It means very impatient. Antsy is only an adjective, not a noun or verb.
None of them are wrong. very is a bland word that really means nothing; it could be replaced with a different adjective
An adjective that means very particular is fussy.
The word huge is an adjective. It means to be very large.
Yes, it is. It means very strange, unusual, and/or scary.
"Gustatory" means "related to the sense of taste," but as I would not classify it as "very rare, you might have a different word in mind.
No, but descriptive is. Descriptive means describing as in "He gave a very descriptiveminute by minute account of his adventure"
No, but they are related conceptually. Diversity is a noun and different is an adjective so they work differently in sentences. The equivalent adjective to "diversity" is "diverse", which still doesn't mean "different". A group is diverse if the individuals are mostly or all different from each other. "Very diverse" does not mean that the individuals are very different from each other but rather that very few of them are the same.
different is an adjective
The word profound is an adjective. It means very deep or serious.