Forest where the Men of the House of Haleth dwelled in Beleriand, often called the Forest of Brethil (S/147). It is simply brethil¹ “silver-birch” used as a name (Ety/NEL).

Conceptual Development: This name appeared in the Silmarillion drafts from the 1930s (SM/115 note #11, LR/261). N. Brethil appeared in The Etymologies, along with a variant N. Brethorn “Forest of Brethil” (Ety/NEL, EtyAC/NEL).