altering vs sterilization

altering and sterilization both are nouns.

Word	Noun	Adjective	Verb	Adverb
altering	Yes	No	No	No
sterilization	Yes	No	No	No

As nouns, sterilization is a hypernym of altering; that is, sterilization is a word with a broader meaning than altering:

altering: the sterilization of an animal
sterilization: the act of making an organism barren or infertile (unable to reproduce)

Other hypernyms of altering include sterilisation.

altering (noun)	sterilization (noun)
the sterilization of an animal	the act of making an organism barren or infertile (unable to reproduce)
	the procedure of making some object free of live bacteria or other microorganisms (usually by heat or chemical means)