hellë noun "sky" (3EL; a distinct word hellë "frost" was struck out, see KHEL.)
eldanoun. Elf, Elf, (lit.) one of the Star-folk, Elven, one of the Star-folk, Elves in general
The most common Quenya word for “Elf”. Its literal meaning is “one of the Star-folk” (WJ/374), a name given to them by Oromë (S/49) and derived from the same primitive root √EL as Q. elen “star”. Strictly speaking, this term excludes the Avari who chose not to journey to Valinor, so that the proper term for all of Elvenkind is Q. Quendë “one of the Elven race”. The Elves of the West rarely encountered the Avari, however, so that term Elda was ordinarily broad enough to describe all Elves.
Conceptual Development: This word dates back to the earliest stages of Tolkien’s languages. At its first appearance, ᴱQ. Elda was glossed “a beach-fay” (QL/35), but was soon extended to describe all Elves (LT1/113). In Tolkien’s earliest writings the word was not given a clear etymology. In the Lhammas “Account of Tongues” from the 1930s (LR/168-180), Tolkien gave ᴹQ. Elda the sense of “one who departed” (LR/169), as opposed to the ᴹQ. Lembi “Lingerers” who remained behind (precursors of the Avari). With this sense, Elda was derived from ᴹ√LED “go, fare, travel” (Ety/LED).
Tolkien soon revised the etymology of Elda so that it was derived instead from ᴹ√ELED “star-folk” (Ety/ELED). In some later writings, he considered both etymologies of this word to be valid, so that Elda was blending of both “star-folk” (from √EL) and Q. Eldo “marcher” (from √LED or √DEL¹), as discussed in the “Quendi and Eldar” essay from 1959-60 and elsewhere (WJ/362-3, PE17/139). However, the sense “star-folk” is probably better known.
In some notes from 1957, Tolkien considered deriving this word from a variant root √DEL² “fair” so that its meaning would be “the fair” (PE17/151), but this seems to have been a transient idea.
quendë noun "Elf", the little-used analogical sg. of Quendi, q.v. (KWEN(ED), WJ:361)
ilwë noun "sky, heavens" (LT1:255), "the middle air among the stars" (LT1:273). VT49:51, 53 also mentions an obscure prononominal element ilwë.