Q. Irildë f. “?Beloved Brilliance”
The original Quenya name of Idril (WJ/235), a derivative of the roots √ID and √RIL (PE17/112), perhaps meaning something like “*Beloved Brilliance”. This name sometimes appeared as Írildë with a long Í (PE17/112, TAI/193), a form of the name that was also given to the sister of Hallatan: see Írildë.
Conceptual Development: In the earliest Lost Tales, this name first appeared as ᴱQ. Irilde (LT2/216), though at this stage it was translated “Mortal Maiden” (LT2A/Idril, GL/50). ᴹQ. Irilde appeared in The Etymologies from the 1930s as a cognate of N. Idhril (Ety/KYELEP); at this point Idhril (Idril) was given as a derivative of ᴹ√ID (Ety/ID).
Later still, Tolkien became dissatisfied with the etymology of Idril and changed her Quenya name to Q. Itarillë; see that entry for that name for further details.
References ✧ PE17/112; TAI/193; WJ/235; WJI/Idril
|Írildeo||genitive||“of Idril”||✧ TAI/193|
|√ID||“desire, long for”||✧ PE17/112 (ID); PE17/112|
|√RIL||“brilliant (light), brilliance”||✧ PE17/112 (RIL); PE17/112|
ᴹQ. Irilde f. “Idhril”
Reference ✧ Ety/KYELEP ✧ “Idhril”
ᴱQ. Irilde f. “Mortal Maiden”
References ✧ GL/50; LT2/216; LT2A/Idril; LT2I/Irildë; PE13/99, 103-104; PE15/27