Biblical transliterations have always been tough for etymologists, and armageddon is no exception. Officially stylized Armageddon with a capital A, the word appears in Revelation 16:16 as part of a prediction concerning the end of humanity. Though it's a little unclear, Armageddon seems to be the name of the mountain where evil spirits meet to destroy us all. In the original Hebrew, the spelling was har megiddo, and it meant "mount Megiddo", megiddo being a proper noun. Since both har and megiddo are very old words, it's hard for philologists to look into them. One research paper said that "they generally regard the etymological problem as being unsolvable". There have been attempts, however. Har seems to be a very basic word that's stuck around for a while, and megiddo has several suggested meanings. It's been theorized that it was the name of a local town, it was a word for "slaughter" connected to Hebrew gadad ("cut"), it meant "invading", and that it was a compound of two words, ultimately meaning "gather" and "cut". Either way, it doesn't sound good and probably traces to Proto-Semitic and Afro-Asiatic.
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.