cardinal numeral + emphatic particle
Analysis. pañca 'five' + api 'even, also' — emphatic form stressing the number itself or preceding clause, 'even five', 'as many as five'.
Etymology. pañca from Indo-European *penkʷe, seen in Sanskrit pañca, Latin quinque, Greek pente, English five, German fünf. The root is ancient and widespread across IE languages denoting the count of fingers on one hand.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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