The original name of Thingol, which in Sindarin became Elu (S/291). Its initial element is él “star” and its final element is the suffix -wë common in ancient names (PM/340).
Conceptual Development: In the earliest Lost Tales, the leader of the third tribe of Elves was named Sol. Ellu (LT1/155), though at this early stage the character was distinct from the contemporanerous character that would develop into Thingol (G. Tinwelint). The name changed to (Telerin?) Elu with one l in very early Silmarillion drafts (SM/13, 85), and was given the Qenya cognate of ᴱQ. Elwe.
In the Annals of Beleriand from the 1930s, ᴹQ. Elwe was identified as the brother of Thingol (SM/264) and so remained in Silmarillion drafts of that period (LR/217). In The Etymologies, ᴹQ. Elwe was first derived from the root √ƷEL “sky”, with a later note indicating it should be transferred to √EL “star” (Ety/ƷEL). It was not until Silmarillion revisions from the 1950s-60s that this name was assigned to Thingol, at which point his brother was renamed to Q. Olwë (MR/82).
Elwë masc. name, *"Star-person" (PM:340, WJ:369, WEG, VT45:12). In the pre-classical Tengwar system presupposed in the Etymologies, Elwë was also the name of a Tengwa similar in form to Roman c, which in a full-vowel mode denoted a (short) e. (VT45:17; in the Sindarin "Mode of Beleriand", exemplified in the LotR itself, this letter has the value a instead. Elsewhere in the Etymologies itself, this symbol is called Ossë [q.v.] and is assigned the value o.)