castration vs neutering

castration and neutering both are nouns.

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

As nouns, neutering is a hypernym of castration; that is, neutering is a word with a broader meaning than castration:

Other hypernyms of castration include altering, fixing.

castration (noun)	neutering (noun)
neutering a male animal by removing the testicles	the sterilization of an animal
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