This etymology is missing or incomplete. Please add to it, or discuss it at the Etymology scriptorium. Particularly: “Related to акв(akw) and па̄лн(pāln).”
Afanasʹjeva, K. V., Sobjanina, S. A. (2012) “акв-па̄лн”, in Školʹnyj mansijsko-russkij slovarʹ) [Mansi-Russian school dictionary], Khanty-Mansiysk: RIO IRO
“акв-па̄лн”, in Northern Mansi-Hungarian dictionary, Tromsø: University of Tromsø, 2023