Qenya
ar-
prefix. outside, beside
ar
conjunction. and; but
aia-
prefix. other, different (of larger numbers)
are
noun. day
yo
conjunction. and
ala
noun. day
ara
preposition. outside, beside
aran
noun. king
au-
prefix. without
ava-
prefix. without
ette
adverb/adjective. outside
lai
adverb. very
ye
conjunction. and
yu
conjunction. and
A prefix for “other, different” appearing Demonstrative, Relative, and Correlative Stems (DRC) from 1948 (PE23/99). Tolkien considered several prior forms on the page where it appeared: {asta} >> {aia < asya} >> aia < ᴹ√AYA (PE23/99 note #27). Earlier drafts had {ar} (PE23/101 note #36) >> {ap-, apana-} >> {war- < gwar-} (PE23/102 note #36). Forms appearing in the rest of the document mostly showed {war(a)-} >> ai(a)-.
Neo-Quenya: For purposes of Neo-Quenya, I would use later hya- as the basis for “other” words, as with (pron.) hya “other thing” and (adj.) hyana “other” (VT49/14).