cardinal numeral + enclitic particle
Analysis. dasa (ten) + api (also, even) — 'ten also' or 'even ten', emphasizing the number or introducing an additional instance of ten.
Etymology. dasa is from PIE *dekm̥ (ten); cognates include Sanskrit daśa, Greek deka, Latin decem, English ten, German zehn. The form api is an enclitic particle meaning 'also; even', unrelated to dasa but used to add emphasis or introduce alternatives.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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