Úr-anar noun, word occurring in Fíriel's Song, translated "the red sun"; actually the prefixed element úr- must have to do with the element ur- "heat, be hot" mentioned in the Silmarillion Appendix. Also compare Ûr as an early Qenya word for "the Sun".
Quenya
urya-
be hot
urya-
verb. to be hot, to be hot; [ᴹQ.] to blaze, [ᴱQ.] burn (intransitive)
úr-anar
the red sun
úrë
noun. heat
The name of tengwa #36 [.] in The Lord of the Rings Appendix E (LotR/1123), a derivative of √UR “heat” (PE22/160). This name probably reflects its use for u-diphthongs in Tengwar spelling.
Conceptual Development: In the 1st edition of The Lord of the Rings the name of tengwa #36 was úr “heat” (RC/736), and in earlier documents on The Feanorian Alphabet this word was glossed “fire, heat” (PE22/51) or just “fire” (PE22/23); see the discussion under ᴹQ. úr for further details.
asta-
to heat, bake (by exposure to sun)
asta- (2) vb. "to heat, bake (by exposure to sun)" (PE17:148)
úr
noun. heat
úrimë
heat
Úrimë (in some editions Urimë, but this seems to be an error; cf. úrë "heat") noun, name of the eighth month of the year, "August" (Appendix D, SA:ur-, UT:302)
úrë
heat
úrë noun "heat", also name of tengwa #36 (Appendix E)
urya- vb. "be hot" (PE17:148), "burn" (intransitive) (LT1:271)