past participle + enclitic particle (sakka + api)
Analysis. sakko (past participle of √sak, 'be able') + api (enclitic 'even, also'); the combination means 'even if able' or 'if it is possible that'—used to introduce a concessive or conditional clause.
Etymology. √sak cognate with Sanskrit śak- and English 'sake' (in the sense of power or capability); api is an ancient enclitic particle (cognate with Latin ap- in compounds, Greek apo-), here reinforcing possibility or permission.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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