The story
- French · borrowed frommézail
- Old French · derived frommuçaille“concealment”
- English todaymesail
Probably from Old French muçaille (“concealment”), via French mézail; only attested in English since the 1800s (also spelled mezail, mursail). Alternatively, a connection to muzzle has also been suggested.
Etymology from Wiktionary, CC BY-SA 4.0.