A comptoller, a type of elected financial officer, pretty obviously comes from the word controller. The catch here is that it's a mistake: folk etymology altered the title from controller (which in the old times, was always financial) to comptroller under the influence of the French word compte, which meant "account", the kind of thing comptrollers deal with. They changed this because they thought it to be correct, never stopping to think of the root control in the word, which means that it was idiotically and accidentally altered. Now, the verb control comes from the Old French term contrerole, which meant "register", because of that's where your assets that are controlled by the bank are held. Before that, it derived from Latin contrarotula, literally meaning "against wheel" because those registers would have a little wheel in them. Contra ("against") is ironically from com-, which meant "with", from the PIE root kom, meaning "beside". Rotula ("wheel" or occasionally "roll") is from the simpler form rota, from Proto-Indo-European hret, which meant "to roll", as a verb. Make sure comptrollers don't control your rolls of money, or we'll be in an etymological cycle with no way to escape.
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.