altering vs castration

altering and castration both are nouns.

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

As nouns, castration is a hyponym of altering; that is, castration is a word with a more specific, narrower meaning than altering:

Other hyponyms of altering include emasculation, spaying.

altering (noun)	castration (noun)
the sterilization of an animal	neutering a male animal by removing the testicles
	surgical removal of the testes or ovaries (usually to inhibit hormone secretion in cases of breast cancer in women or prostate cancer in men)
	the deletion of objectionable parts from a literary work