The hidden fortress city of the Noldor called the “Caverns of Narog” (S/114) and described as “the great underground burg and halls upon the river Narog” (WJ/414). This name is a combination of the river name Narog and othrond “underground stronghold” (WJ/414).
Conceptual Development: This name first appeared in Lays of Beleriand from the 1920s as ᴱN. Nargothrond (LB/36) and it remained the same thereafter. The name N. Nargothrond appeared in The Etymologies from the 1930s with the translation “fortress of Narog” and the derivation given above (Ety/NÁRAK, OS, ROD). In Notes on Names (NN) from 1957, Tolkien considered deriving the name from its Khuzdul equivalent N. Nar(u)kuthûn (PE17/47), but elsewhere he stated that the Dwarvish name for the caverns was Nulukkhizdîn (S/230, WJ/180).
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