neuter singular nominative, or abstract noun; past participle passive (gerundive) of pāpuṇāti 'to reach, obtain'
Analysis. patta- (past participle of pāpuṇāti 'reached, obtained') + -abba (gerundive suffix, marking fitness or obligation). The form expresses what is worthy of attainment or what should be sought.
Etymology. From √pāp (Sanskrit pra-āp, 'to arrive, reach'); the gerundive -abba is cognate with Sanskrit -avya (Latin -abilis, English -able). The concrete sense 'reached' extends to 'what should be reached, a proper aim or goal'.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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