countermand vs revoke

countermand and revoke both are nouns.

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

As verbs, countermand and revoke are synonyms defined as:

Other synonyms of countermand include annul, lift, overturn, repeal, rescind, reverse, vacate.

countermand (noun)	revoke (noun)
a contrary command cancelling or reversing a previous command	the mistake of not following suit when able to do so

countermand (verb)	revoke (verb)
cancel officially	cancel officially
	fail to follow suit when able and required to do so