write off vs cancel

write off is not a noun while cancel is a noun.

Word	Noun	Adjective	Verb	Adverb
write off	No	No	Yes	No
cancel	Yes	No	Yes	No

As verbs, cancel is a hypernym of write off; that is, cancel is a word with a broader meaning than write off:

Other hypernyms of write off include strike down.

write off (noun)	cancel (noun)
	a notation cancelling a previous sharp or flat

write off (verb)	cancel (verb)
reduce the estimated value of something	make invalid for use
concede the loss or worthlessness of something or somebody	remove or make invisible
write something fluently, and without hesitation	declare null and void; make ineffective
cancel (a debt)	postpone indefinitely or annul something that was scheduled
	make up for