spay vs alter

spay and alter both are verbs.

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

As verbs, spay and alter are synonyms defined as:

Other synonyms of spay include castrate, neuter.

spay (verb)	alter (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