pronoun, nominative/accusative plural with emphatic particle
Analysis. tumhe (accusative plural of tumha "you") + api (emphatic particle "even, also"); the sandhi contracts api to pi after the vowel-final tumhe.
Etymology. tumha is the Pali reflex of PIE *tu- "you" (compare Sanskrit tvam, Latin tu, Greek su, English thou). The emphatic particle api derives from PIE *op- "back, toward" (related to Sanskrit api, Latin ob-), originally "in return, back again", hence "also, even".
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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