Nobody's exactly sure how long jalapeño peppers have been cultivated, but it's probably been around for thousands of years, with confirmed cultivation dating back to the time of the Aztecs. Surprisingly, the food wasn't brought to the United States until the 1940s, but since its introduction, usage of the word has been increasing fairly linearly. The name literally means "from the region of Xalapa" (which is sometimes spelled with a J), because there was a lot of farming of the pepper in that area. Xalapa is Nahuatl for "sand by the water", and that word is composed out of xalli, meaning "sand", atl, meaning "water", and -pan, meaning "place". Beyond that, we can't reconstruct anything due to a lack of written records, but the terms probably come an Uto-Aztecan proto-language.
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.