ind. (sandhi form athopi)
Analysis. atho + api (sandhi contraction): 'and' + 'also/even', yielding 'and also, and even, or moreover'.
Etymology. atho is an old indeclinable particle of coordinate conjunction; api is the enclitic 'also, even' (from √ap- 'to reach, attain', concretely 'what reaches along with'). The compound strengthens the conjunction with an additive sense.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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