A hypothetical early root to explain words in the Gnomish Lexicon of the 1910s such as G. fedhin “bound by agreement; ally, friend” and G. fedhwen “treaty” (GL/34). There are some Early Noldorin words from the 1920s of similar form, such as ᴱN. fedhui (PE13/142), but they are unglossed so it is unclear whether they retained the same meaning. There are no further signs of this root in Tolkien’s later writing.
root. *law, bond