Today I quite accidentally, and equally whimsically, walked into a concert of church bells at Yale University. There, I learned that carilloneur is the word for the person making those sounds, and (by extension) that they play it on the carillon, a keyboard of sorts that corresponds to 23 bells in the belfry. This got me interested in the etymology of carillon, and it truly is fascinating. Apparently this comes from French, where the Old French word was quarrillon. This actually meant "set of four bells", which makes it nineteen short of the modern carillon, but bells were probably way harder to get back in the day anyway. Quarillon derives from Latin quaternionem, which just meant "set of four" and could refer to a quartet of just about anything. No bells, specifically; that was an implication that was established later. Clearly, you can see where this is going: quaternionem is basically a conjugation of quater, meaning "four", which may be reconstructed to the Proto-Indo-European root kweter, or "four" as well.
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.