demagnetise vs alter

demagnetise and alter both are verbs.

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

As verbs, alter is a hypernym of demagnetise; that is, alter is a word with a broader meaning than demagnetise:

Other hypernyms of demagnetise include change, modify.

demagnetise (verb)	alter (verb)
make nonmagnetic; take away the magnetic properties (of)	remove the ovaries of
erase (a magnetic storage device)	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