The word calzone was first used in the United States in 1933, but it was coined in Italian all the way back in the eighteenth century when the food was invented. The term had a literal definition of "trouser leg", apparently because of visual similarity. That's from the earlier word calza, meaning "sock", which comes from Latin calceus, meaning "shoe". The root there is calx, the word for "heel", and the suffix -eus, which is just the masculine nominative suffix. Calx, which is unrelated to the word for "limestone", has an uncertain origin, but it might be from Proto-Indo-European kel ("to bend"), from PIE khlk ("hip"), or even Etruscan. Usage of the word calzone peaked in the mid-1990s.
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.