The word flannel was first used in a 1503 ledger detailing the expenses of Elizabeth II, the wife of King Henry VII. There, if was spelled fflanell, and other spellings at the time included flannen, flannion, flannin, flanning, and flanell. Because of the structure of the word and the etymological timeline, the Oxford English Dictionary suggests that fflanell comes from Welsh gwlanen, which also meant "flannel". That would come from their word for "wool", gwlan, which ultimately derives from Proto-Celtic wlana and Proto-Indo-European hwlhneh, both also meaning "wool". An alternative origin proposed by some linguists who disagree with the theorized sound changes is that flannel comes from the Old French noun flaine, describing a type of wool. For now, I'll stick with the OED explanation.
Hello! I'm Adam Aleksic, a sophomore studying government and linguistics at Harvard University, where I co-founded the Harvard Undergraduate Linguistics Society. In addition to etymology, I also really enjoy politics, vexillology, geography, board games, conlanging, and law.