I found this out while finishing up my latest infographic (which is now on the corresponding page): the word clavicle, being the scientific term for the bone stretching from your shoulder to your sternum, has fascinating origins. First, it derives from the French word clavicule, which meant "collarbone", from its Latin cognate. This was kind of a metaphorical usage of the earlier Latin word clavicula, which meant "small key", sort of because the clavicle fits in like a key. This is from the earlier word clavis (clearly also the source of Spanish llaves), also defined as "key". This probably comes from the Proto-Indo-European word klehw, "hook" through Proto-Italic klawis, but an alternative theory pegs clavicle as from the same root but through the Greek word for "key", klis. I guess we'll never "unlock" this mystery, but if anyone ever does, it will be the "key" to linguistic success.
Adam Aleksic, a freshman studying linguistics at Harvard University, has been described as the internet's sixth most famous etymologist. He has disturbing interests in words, vexillology, geography, board games, limericks, and law, and he loves writing about himself in the third person.
The Etymology Nerd