Middle Primitive Elvish
pher(en)
root. beech
pheren
noun. beech-tree
bereth
root. beech
kyul(u)mā
noun. mast
tyulmā
noun. mast
Beware, older languages below! The languages below were invented during Tolkien's earlier period and should be used with caution. Remember to never, ever mix words from different languages!
A root in The Etymologies of the 1930s serving principally as the basis for N. brethil “beech” (Ety/BERÉTH). In the notes from the late 1950s or early 1960s Tolkien instead connected brethil to the root √BARATH and S. bereth “queen”, where it had the true meaning of “princess” (PE17/23). But that could be a later association rather that a genuine etymology, and doesn’t necessarily invalidate ᴹ√BERETH (especially given the other phonological issues with S. bereth < √BARATH).