Grammatical Analysis
Khayāñāṇa: [nt.] knowledge of destruction; knowledge of exhaustion. Formed by khaya (destruction, exhaustion, ending) + ñāṇa (knowledge, profound insight).
Orthodox Definition
Khayāñāṇa is a supreme, supramundane cognitive achievement unique to the fully awakened. It is the absolute, experiential knowledge that flashes within the mind of an Arahat confirming that all defilements (kilesa), influxes (āsava), and fetters (saṃyojana) have been utterly destroyed and exhausted.
In the standard sutta descriptions of awakening, when a practitioner reaches the pinnacle of meditation, they first verify the destruction of the influxes, giving rise to Khayāñāṇa. This knowledge is what prompts the famous “lion’s roar” (sīhanāda) of the Arahat: “Khīṇā jāti, vusitaṃ brahmacariyaṃ, kataṃ karaṇīyaṃ, nāparaṃ itthattāyā’ti pajānāti” (Destroyed is birth, the holy life has been lived, what had to be done has been done, there is no more coming to any state of being).
It is intrinsically paired with Anuppādāñāṇa (the knowledge of non-arising) to form the complete cognitive profile of final liberation.
Textual References
- Sutta: Sāmaññaphala Sutta (DN 2) – Listing the knowledge of the destruction of the taints as the absolute, highest fruit of the contemplative life.
- Canonical: Paṭisambhidāmagga (Ñāṇakathā) – Deep analytical tracking of the insight knowledges terminating in destruction.
- Commentary: Visuddhimagga (Chapter XXII) – Clarifying how this knowledge operates as a reviewing knowledge (paccavekkhaṇa-ñāṇa) immediately following the attainment of the Arahat Path.