unify vs pair

unify is not a noun while pair is a noun.

Word	Noun	Adjective	Verb	Adverb
unify	No	No	Yes	No
pair	Yes	No	Yes	No

As verbs, pair is a hyponym of unify; that is, pair is a word with a more specific, narrower meaning than unify:

unify (noun)	pair (noun)
	two people considered as a unit
	a set of two similar things considered as a unit
	a poker hand with 2 cards of the same value
	two items of the same kind

unify (verb)	pair (verb)
become one	engage in sexual intercourse
join or combine	bring two objects, ideas, or people together
to bring or combine together or with something else	arrange in pairs
act in concert or unite in a common purpose or belief	occur in pairs
bring together for a common purpose or action or ideology or in a shared situation	form a pair or pairs