topon. Land of Mist, (lit.) Mist-and-Dusk
The Quenya name of NS. Hithlum (S/118). It is usually glossed “Land of Mist”, but it is a compound of hísë (hísi-) “mist” and lómë “dusk”, so a more literal translation would be “Mist-and-Dusk” (given as a translation of Hithlum on LR/406).
Conceptual Development: This name dates back to the earliest Lost Tales, where ᴱQ. Hisilóme was translated “Shadowy Twilights” (LT1/112). In Silmarillion drafts from the 1930s, ᴹQ. Hisilóme was translated “Twilit Mist” (SM/4) and “Land of Mist” (SM/101). The name appeared in the Etymologies with the same form but a slightly different derivation, with its second element originally derived from ᴹQ. lumbe “gloom, shadow” (Ety/LUM).