twin vs birth

twin and birth both are nouns.

Word	Noun	Adjective	Verb	Adverb
twin	Yes	Yes	Yes	No
birth	Yes	No	Yes	No

As verbs, birth is a hypernym of twin; that is, birth is a word with a broader meaning than twin:

Other hypernyms of twin include bear, deliver, give birth, have.

twin (noun)	birth (noun)
a duplicate copy	the event of being born
either of two offspring born at the same time from the same pregnancy	a baby born; an offspring
	the process of giving birth
	the kinship relation of an offspring to the parents
	the time when something begins (especially life)

twin (adjective)	birth (adjective)
being two identical

twin (verb)	birth (verb)
give birth to twins	cause to be born
grow as twins
bring two objects, ideas, or people together
duplicate or match