papers vs brevet

papers and brevet both are nouns.

Word	Noun	Adjective	Verb	Adverb
papers	Yes	No	No	No
brevet	Yes	No	Yes	No

As nouns, brevet is a hyponym of papers; that is, brevet is a word with a more specific, narrower meaning than papers:

papers: writing that provides information (especially information of an official nature)
brevet: a document entitling a commissioned officer to hold a higher rank temporarily (but without higher pay)

papers (noun)	brevet (noun)
writing that provides information (especially information of an official nature)	a document entitling a commissioned officer to hold a higher rank temporarily (but without higher pay)

papers (verb)	brevet (verb)
	promote somebody by brevet, in the military