The word bandit was first attested in English in Shakespeare's Henry IV, Part 2 (written at an unknown point in the late 1590s). There, he spelled it bandeto, and subsequent forms included bandetto, bandito, and bandite. These words hint at its origin from the Italian word bandito, which meant "outlaw", same as today. That's the past participle of bandire, a verb meaning "banish", since outlaws are people banished from society. That traces to the Vulgar Latin verb bannire, meaning "to proclaim" (the connection was that people were banished through proclamations), and the d might have been added because of influence from a similar Gothic word. Finally, bannire (also the source of ban and banish) derives from the Proto-Indo-European root bha, meaning "to speak".
Hello! I'm Adam Aleksic. This year, I graduated from Harvard University with a degree in Government and Linguistics. There, I co-founded the Harvard Undergraduate Linguistics Society and wrote a thesis on Serbo-Croatian language policy, magna cum laude. In addition to etymology, I also really enjoy philosophy, trivia, vexillology, geography, board games, conlanging, art history, and law.