feminine noun, instrumental/locative form with iti (quotative particle)
Analysis. ā + kiñcaññā + āyatana + upapatti, iti — a compound designating rebirth into one of the four formless spheres (arūpaloka), specifically the sphere where consciousness alights on 'nothingness' itself as its object. The instrumental ākiñcaññāyatanūpapattiyā governs a preceding verb of becoming or passing, and iti marks the quoted or cited state.
Etymology. ākiñcaññā is a-kiñcañña, 'not-something' (negation a- + kiñca 'anything' + abstract suffix -ñña); āyatana is ā + yatana, 'extension, dimension' (from ā 'toward' + yam 'stretch', related to English yoke, Sanskrit yoga); upapatti is upa- + patti, 'reappearance, rebirth' (upa 'close, near' + pad 'obtain', cognate with Latin petere 'seek'). Together the compound names the attainment of rebirth in the realm where the meditator's object of focus is emptiness itself—a classical Buddhist cosmological term appearing throughout the Nikāyas.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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