The bow of Beleg (S/208).

Conceptual Development: This name first appeared in the Lays of Beleriand from the 1920s as ᴱN. Balthronding (LB/117, 127). The form Balthronding also appeared in The Etymologies from the 1930s (Ety/STARAN), along with Belthronding (Ety/BEL, DING), in both cases designated an Ilkorin name. As an Ilkorin word, it was a combination of bel “strength”, thrôn “stiff, hard” and ding, an onomatopoeic sound, but it is unclear whether this derivation remained valid in Tolkien’s later writing.