John Montagu, the Fourth Earl of Sandwich, had a particular affinity for gambling. His addiction was so bad that he refused to get up for meals, ordering his servants to make him his favorite snack, pieces of meat between two slices of bread. Since Montagu was pretty well-known, the sandwich got named after him, and, in an unrelated occurrence, James Cook also named the Sandwich islands in the South Atlantic after Montagu as well. Sandwich was a town in Kent, but before that it was a surname, literally meaning "sand settlement". The first part of the name, sand, comes from Proto-Indo-European bhes (a verb with the definition "to rub"), through Proto-Germanic sandam (also "sand"). The later part of the name, -wich, is pretty common in England, as we can see with place names like Norwich and Greenwich. That's because it meant "settlement". By way of Germanic alterations like wic and wik, it derives from Latin vicus and ultimately traces to Proto-Indo-European weyks, still meaning something like "village".
Adam Aleksic, a rising sophomore studying linguistics and government at Harvard University, has been described as the internet's sixth most famous etymologist. He also has disturbing interests in politics, vexillology, geography, board games, conlanging, and law.