sandhi contraction: demonstrative pronoun idaṃ + enclitic particle api
Analysis. idaṃ (this) + api (even, also, just). The enclitic api emphasizes or restricts the demonstrative to its precise referent: 'this and nothing else' or 'even this'. Common in the Suttas to mark a specific case or instance.
Etymology. idaṃ derives from PIE *i-/e-d- (see, point: the root of 'id' and 'ideo' in Latin). api is a particle akin to Sanskrit api, from PIE *apo- (off, away), originally meaning 'further away' but becoming an emphatic enclitic 'even, just, also'.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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