únótimaadj. "not possible to count, countless" (VT39:14), pl. únótimë (translated "numberless") attested (ú-nót-imë "not-count-able") (Nam, RGEO:66, Appendix E). Cf. unnegated nótima, q.v.
unqua("q") adj. "hollow" (UNUK)
unqualë("q") noun "agony, death" (KWAL, VT45:36). See anqualë. In the pre-classical Tengwar system presupposed in the Etymologies, unqualë was the name of letter #8 (VT45:18), which tengwa Tolkien would later call ungwë instead – changing its Quenya value from nqu to ngw.
unquënoun "hole, hollow" (VT46:20, UNUK), also name of tengwa #16 (Appendix E; there spelt unque, while the Etymologies has unqe)
untúpavb. "down-roofs" = covers (perhaps for *undutúpa-, cf. undu-). Present tense of untup- with lengthening of the stem vowel and the suffix -a (cf. síla "shines" from sil-)
unuhuinëprep + noun "under-shadow" (LR:47); see huinë.
unutixë("ks") noun dot or point placed below the line of writing (TIK). In the Etymologies as printed in LR, the initial element unu- was misread was nun- (VT46:19). The variant unutexë("ks") was rejected by Tolkien (VT46:20)
únyárimaadj. "impossible to recount" (because all the facts are not known, or the tale is too long) (WJ:370)