A word that is an element in Avallónë “Outer Isle” (S/260). ᴹQ. ava was glossed “outside, beyond” in The Etymologies of the 1930s under from the root ᴹ√AWA “away, forth; out” (Ety/AWA), and it was glossed “outer, exterior” in notes on the Ambarkanta from the early 1930s (SM/241). Give its root, it likely means “outer” in the sense “further away”.
Quenya
Avacúma
exterior void beyond the world
ava
adverb/adjective. *outer, [ᴹQ.] outside, beyond; outer, exterior
etsë
outside, exterior
etsë noun "outside, exterior", glosses changed from ?"issuing" and ?"spring" (VT45:13)
ar-
outside
ar- (1) prefix "outside" (AR2), element meaning "beside" (VT42:17), "by" (PE17:169; in the same source the glosses "near, by, beside" were rejected). Cf. ara.
ara
outside, beside, besides
ara prep.(and adv.?) "outside, beside, besides" (AR2, VT49:57). According to VT45:6, the original glosses were "without, outside, beside", but Tolkien emended this. Arsë "he is out", VT49:23, 35, 36. As for ar(a), see ar #1. VT49:25 lists what seems to be ar(a) combined with various pronominal suffixes: Singular anni > arni "beside me", astyë "beside you" (informal), allë "besides you" (formal), arsë "beside him/her", plural anwë > armë "beside us" (exclusive), arwë "beside us" (inclusive), astë > ardë "beside you" (plural), astë > artë "beside them"; dual anwet > armet "beside us (two)". (Here Tolkien presupposes that ara represents original ada-.) The same source lists the unglossed forms ari, arin that may combine the preposition with the article, hence "beside the" (VT49:24-25)
ava
outside, beyond
ava (1) adv.? noun? prep.? "outside, beyond" (AWA, VT45:6)
ettë
outside
ettë noun(and/or adv.?) "outside" (ET)
Avacúma place-name, "Exterior Void beyond the World" (AWA, (OY) )