The original name of the Vanyar as first tribe of the Elves (WJ/380), a name they sometimes still used to refer to themselves (WJ/382). This name is simply the adjective minya “first” used as a plural noun.
Quenya
minya
first
minya
first; eminent, prominent
minyar
collective name. Firsts (original clan name of the Vanyar)
minyatur
masculine name. First-ruler
minyarussa
masculine name. First-russa
Minyarussa
first-russa
Minyarussa noun "First-russa", masc. name (VT41:10)
Minyatur
first-ruler
Minyatur noun "First-ruler"; Tar-Minyatur "High First-ruler", title of Elros as the first King of Númenor (SA:minas, PM:348, SA:tur)
Minyon
first-begotten
Minyon noun "First-begotten", attested as a personal (masc.) name (MR:87). Apparently this is minya "first" + the stem ON = beget.
enna
first
[enna adj. "first" (VT45:12)]
esta
first
esta (2) adj. "first" (ESE/ESET); this entry was marked with a query. The word Yestarë (q.v.) "Beginning-day" in LotR suggests that Tolkien decided to change the stem in question to _YESE/YESET_. We could then read *yesta for esta (but later this became a noun "beginning" rather than an adj. "first", PE17:120) and also prefix a y to the other words derived from ESE/ESET (essë* > yessë, essëa > yessëa). Estanossë noun "the firstborn", read likewise Yestanossë** (*Yestanessi?) but in a later text, Tolkien used Minnónar (q.v.) for "the Firstborn" as a name of the Elves, and this form may be preferred. _(In the Etymologies as printed in LR, the word _Estanossë is cited as "Estanesse", but according to VT45:12, the second-to-last vowel is actually o in Tolkien's manuscript.)
inga
first
inga (2) adj. "first" (ING)
setta
first
[setta, setya adj. "first" (possibly also "primary", but Tolkien's gloss was not certainly legible) (VT46:13)]
tereva
fine, acute
tereva adj. "fine, acute" (TER/TERES), "piercing"_ (LT1:255; though glossed "fine, acute" in the Etymologies, the stem _TER is defined as "pierce")
minya adj. "first" (MINI) (cf. Minyatur, Minyon); "eminent, prominent" (VT42:24, 25). Minyar "Firsts", the original name of the Vanyar (or rather the direct Quenya descendant of the original Primitive Quendian name) (WJ:380)