Ainonoun "god", within Tolkien's mythos a synonym of Ainu (but since Aino is basically only a personalized form of aina "holy", hence "holy one", it could be used as a general word for "god") (PE15:72)
Ainunoun "holy one, angelic spirit"; fem. Aini(AYAN, LT1:248); "one of the 'order' of the Valar and Maiar, made before Eä"; pl. Ainur is attested. Adopted and adapted from Valarin ayanūz (WJ:399). In the early "Qenya Lexicon", ainu was glossed "a pagan god", and aini was similarly "a pagan goddess", but as Christopher Tolkien notes, "Of course no one within the context of the mythology can call the Ainur 'pagan' " (LT1:248). Ainulindalënoun "Music of the Ainur" (SA:lin #2), the First History (WJ:406), the Song of Creation (AYAN)
aipionoun "plum tree, cherry tree" (GL:18)
aiqua ("q") adj. "steep" (AYAK). Not to be confused with the pronoun *aiqua “if anything, whatever” that post-Tolkien writers have extrapolated from aiquen (q.v.) on the basis of such pairs as ilquen vs. ilqua (q.v.)
aiqualin ("q") adj. "tall", plural form (???) (MC:216; this is "Qenya" - but cf. aiqua above.)