bandit vs thief

bandit and thief both are nouns.

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

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

bandit: 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 bandit include stealer.

bandit (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