pronoun with emphatic particle api; nominative singular masculine
Analysis. so (he, that) + api (also, even, indeed) = 'he too', 'that very one'; the emphatic particle api reinforces the pronoun's reference to what precedes.
Etymology. so from Indo-European *so- (demonstrative stem), cognate with English 'that', Latin 'is', Greek 'ho'. api is an older emphatic particle, possibly from *apo- 'off, away' (hence 'distinctly, indeed').
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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