1b topon. >> Nargothrond
narogplace name. Narog
A river in Beleriand (S/120), an adaptation of its Khuzdul name narâg meaning “black” (PE17/37).
Conceptual Development: The name ᴱN. Narog first appeared in a marginal note in the earliest Lost Tales (LT2/244, note #15), and was translated “Torrent” in the Lays of Beleriand from the 1920s (LB/61). The adjective ᴱN. narog “violent (of water, rain, etc.), torrential” appeared in Early Noldorin word list from this same period (PE13/150).
In The Etymologies from the 1930s, N. Narog was derived from primitive ᴹ✶narāka “rushing, rapid, violent”, similar to its earlier meaning (Ety/NÁRAK). Its derivation from Khuzdul appeared in Tolkien’s “Words, Phrases and Passages from The Lord of the Rings” from the 1950s-60s (PE17/37). Elsewhere in these notes he considered deriving it from (untranslated) Kh. naruka instead (PE17/47).
thalosplace name. Torrent
One of the seven streams from which Ossiriand got its name (S/123), and is simply thalos “torrent” used as a name (Ety/STAL). Given the river’s location in Ossiriand, this name might be Nandorin instead.
Conceptual Development: In The Etymologies from the 1930s, the name Thalos was designated Ilkorin, with the derivation given above (Ety/STAL). Like many of the river names in Ossiriand, Tolkien did not give a new etymology of the name after he abandoned the Ilkorin language.
In the Etymologies, the river's name was stated to mean "rushing, violent". However, in a later writing by Tolkien, the Sindarin name Narog was given two possible Khuzdul origins: Narâg and naruka, both of unknown meaning. In Eriol's Old English translations, Narog is referred as Hlyda "Loudy". The Elves of Nargothrond were named Hlydingas.
* thalosnoun. torrent
1) oll (mountain steam), pl. yll. (The source also cites the archaic form old.) 2) thorod, pl. theryd (archaic thöryd).