countermand vs cancel

countermand and cancel both are nouns.

Word	Noun	Adjective	Verb	Adverb
countermand	Yes	No	Yes	No
cancel	Yes	No	Yes	No

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

Other hypernyms of countermand include strike down.

countermand (noun)	cancel (noun)
a contrary command cancelling or reversing a previous command	a notation cancelling a previous sharp or flat

countermand (verb)	cancel (verb)
cancel officially	make invalid for use
	remove or make invisible
	declare null and void; make ineffective
	postpone indefinitely or annul something that was scheduled
	make up for