brigand vs thief

brigand and thief both are nouns.

Word	Noun	Adjective	Verb	Adverb
brigand	Yes	No	No	No
thief	Yes	No	No	No

As nouns, thief is a hypernym of brigand; that is, thief is a word with a broader meaning than brigand:

brigand: an armed thief who is (usually) a member of a band
thief: a criminal who takes property belonging to someone else with the intention of keeping it or selling it

Other hypernyms of brigand include stealer.

brigand (noun)	thief (noun)
an armed thief who is (usually) a member of a band	a criminal who takes property belonging to someone else with the intention of keeping it or selling it