Pardon the terrible title pun that half of you won't get. The word avocado was coined in 1763 and referred to the relevant tree when it was brought into English. This was a loanword from Spanish, where the cognate avocado had the same definition, and that in turn is from the earlier term aguacate. This might suggest water (agua), but it's much more interesting than that: this stems (no pun intended) from the Nahuatl word ahuacatl, describing the fruit, specifically. This was a homonym whose secondary definition meant "testicle". Both terms come from the proto-Aztecan word pawa describing the fruit, but somewhere along the line a metaphorical meaning, possibly referring to the shape of the food, emerged. It is even possible that the term we have now comes from the "testicle" definition, but that is unlikely. The proto-Aztecan word probably is from the proto-Uto-Aztecan family, which is only theorized by linguists to exist.
Hello! I'm Adam Aleksic, a sophomore studying linguistics and government at Harvard University, where I founded the Harvard Undergraduate Linguistics Society. I also have disturbing interests in politics, vexillology, geography, board games, conlanging, and law.