alter vs spay

alter and spay both are verbs.

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

As verbs, alter and spay are synonyms defined as:

Other synonyms of alter include castrate, neuter.

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