When the word duffel was first used in some 1649 records from the colony of Connecticut, it was spelled duffle and referred to a kind of woollen fabric. Around the mid-nineteenth century, that was extended to the type of coat made of the material and "camping materials" that tended to be associated with it. Finally, the sense of "duffel bag" emerged in the 1930s. Before that time, the word was spelled duffel and duffle with about the same frequency, but duffle started to emerge as the more popular spelling, although the other form is still valid. The word comes from Duffel, the name of a town in Belgium where the textile was originally sold. That was attested in Middle Dutch as Duffla and might be a combination of the Gaulish word for "water", dubrum, and the Latin word for "place", locus.
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.