A lot of people just assume that the word parsnip is a combination of parsley and turnip. Well, not really. As parsnip developed into existence from the Old French word pasnaie, the -nip ending was indeed added by influence of turnip, but the rest was unique. Anyway, pasnaie (which could also be a euphemism for "penis") comes from Latin pastinaca, which meant both "parsnip" and "carrot". This in turn derives from pastinum, which meant something like "two-pronged fork or spade", because they have a similar shape. Although this has an unknown etymology officially, I'm guessing it comes from a word for "dig" (based on a connection to pastinare, with that meaning), possibly because of the "spade" connection. It might not even be Indo-European; just some wild guesses. Although it was borrowed in the 1300s, the word parsnip has had relatively constant usage since the late 1700s.
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.