Ārūpya-dhātu
ārūpya-dhātu (Sanskrit; Pāli, arūpa-dhātu). The Formless Realm; the most subtle of the three levels of existence (triloka) according to Buddhist cosmology. This realm is totally devoid of all materiality and suffering.
It comprises four states:
boundless space (ākāśa-anantya),
boundless consciousness (vijñāna-anantya),
nothingness (ākiñcanya), and
neither-ideation nor
non-ideation (naivasaṃjñā-nāsaṃjñā).
Birth in these states is achieved through mastery of one of the four corresponding attainments (samāpatti) but despite the extremely tenuous nature of existence in this realm, it still forms part of saṃsāra and beings residing there will eventually return to lower states of existence when the force of their merit (puṇya) or good karma is exhausted.
ārūpya-dhātu: The sphere of immateriality. This is subdivided into four progressive stages (bhūmi):
1.ākāśānantyāyatana,
2.vijñānāntyāyatana,
3.ākiṃcanyāyatana;
4.naivasaṃjñānāsaṃjñāyatana.