confidential vs classified

confidential is not a noun while classified is a noun.

Word	Noun	Adjective	Verb	Adverb
confidential	No	Yes	No	No
classified	Yes	Yes	No	No

confidential (noun)	classified (noun)
	a short ad in a newspaper or magazine (usually in small print) and appearing along with other ads of the same type

confidential (adjective)	classified (adjective)
the level of official classification for documents next above restricted and below secret; available only to persons authorized to see documents so classified	arranged into classes
denoting confidence or intimacy	official classification of information or documents; withheld from general circulation
entrusted with private information and the confidence of another
(of information) given in confidence or in secret