bandit (n.) Look up bandit at
"lawless robber, brigand" (especially as part of an organized band), 1590s, from Italian bandito (plural banditi) "outlaw," past participle of bandire "proscribe, banish," from Vulgar Latin *bannire "to proclaim, proscribe," from Proto-Germanic *bannan "to speak publicly" (used in reference to various sorts of proclamations), "command; summon; outlaw, forbid" (see ban (v.)).

Vulgar Latin *bannire (or its Frankish cognate *bannjan) in Old French became banir, which, with lengthened stem, became English banish.