Quenya 

quelië

noun. *fading

A noun for “fading” indicated by the month name Narquelië “Sun-fading” in The Lord of the Rings appendices and its drafts (LotR/1110; PM/134). It was likely the gerund (verbal noun) of the verb quel- “to fade”.

Conceptual Development: The Declension of Nouns from the early 1930s had ᴹQ. qelesta “dying, fading” (PE21/8).

quelië

waning

quelië noun "waning" in Narquelië, q.v.

quel-

to fail

#quel- ("q")vb. "to fail" (wane, wither, fade; compare the nouns quelië "waning", quellë "fading"), only attested in the future tense (queluva in FS).