poison vs alter

poison is a noun but alter is not a noun.

Word	Noun	Adjective	Verb	Adverb
poison	Yes	No	Yes	No
alter	No	No	Yes	No

As verbs, alter is a hypernym of poison; that is, alter is a word with a broader meaning than poison:

Other hypernyms of poison include change, modify.

poison (noun)	alter (noun)
anything that harms or destroys
any substance that causes injury or illness or death of a living organism

poison (verb)	alter (verb)
administer poison to	remove the ovaries of
add poison to	become different in some particular way, without permanently losing one's or its former characteristics or essence
kill with poison	cause to change; make different; cause a transformation
kill by its poison	insert words into texts, often falsifying it thereby
spoil as if by poison	make an alteration to