accusative singular neuter (used as an adverb)
Analysis. pacc- (past participle stem of paṭi- "back, against") + -atta (reflexive possessive suffix "own"). Literally "one's own back" or "own self", emphasizing personal, direct engagement rather than hearsay or theory.
Etymology. From paṭi- (back, against) + atta (self). The prefix paṭi- originally meant physical counter-motion; here it frames the reflexive pronoun atta to mean "turned back upon oneself", hence one's own direct experience. Sanskrit prati-ātma follows the same logic.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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