religious vs devout

religious is a noun but devout is not a noun.

Word	Noun	Adjective	Verb	Adverb
religious	Yes	Yes	No	No
devout	No	Yes	No	No

religious (noun)	devout (noun)
a member of a religious order who is bound by vows of poverty and chastity and obedience

religious (adjective)	devout (adjective)
having or showing belief in and reverence for a deity	deeply religious
of or relating to clergy bound by monastic vows	sincerely earnest
concerned with sacred matters or religion or the church
extremely scrupulous and conscientious