A Sindarin word for “star” that is largely archaic and poetic, and is mainly used as element in names like Elrond (Let/281; WJ/363; Ety/EL); the more usual word for “star” in ordinary speech was gil (RGEO/65). However, the collective form elenath is still used in common speech to refer to the entire host of stars (WJ/363). The plural of êl is elin, as this word was derived from ancient ✶elen, and the final n that was lost in the singular was preserved in the plural. In some cases Tolkien posited a restored analogical singular elen from the plural form (PE17/24, 67, 139), but this isn’t in keeping with the notion that the word was archaic, so I would ignore this for purposes of Neo-Sindarin.
Conceptual Development: This word and its root first appeared in The Etymologies of the 1930s, where N. el “star” was derived from the root ᴹ√EL of similar meaning, but was “only [used] in names” (Ety/EL). It seems Tolkien introduced the root to give a new etymology for names like N. Elrond and N. Elwing, which initially appeared under the root ᴹ√ƷEL “sky” (Ety/ƷEL).
pl1. elin, pl2. elenath** ** n. star. Q. elen, pl1. eldi, eleni, pl2. elelli. >> elen