ᴹ√UY root. “*long trailing plant”
An unglossed root in The Etymologies of the 1930s with derivatives like ᴹQ. uile “long trailing plant, especially seaweed” and N. uil “seaweed” (Ety/UY). In this document it also was the basis of the name of the Vali ᴹQ. Uinen, but in later writings Tolkien said this name was not Elvish, but was adapted from Valarin (WJ/404). This may mean the root ᴹ√UY was abandoned, but I would retain it for purposes of Neo-Eldarin to preserve these 1930s words for “seaweed”.
References ✧ Ety/NEN, UY