The most common Quenya word for “star”, mentioned very frequently, derived from an extended form ✶elen of the root √EL “behold” (PE17/67; WJ/360, 362). Its usual plural form is eleni, but it has an archaic plural †eldi sometimes used in verse, the result of the Ancient Quenya sound whereby [[aq|[ln] became [ld]]] after the ancient plural underwent the Quenya syncope, ✶elenī > AQ. elni; its normal modern plural form eleni was actually a reformation from the singular (PE17/57, 151; WJ/362).
Conceptual Development: This word first appeared in The Etymologies of the 1930s, though in the original entry for the root ᴹ√EL Tolkien said it was poetical and gave variants ellen and elena (Ety/EL).
elena adj. "of the stars" (SA:êl, elen); also elenya