interrogative pronoun, nominative singular masculine; part of a pairing with ānanda in apposition or vocative address
Analysis. katamañcānanda is a rhetorical pairing joining katama (which? what?) with ānanda (Ānanda, the Buddha's cousin), most likely "Which one, Ānanda?" — a common formulaic opening in suttas where the Buddha poses a question to Ānanda before answering it himself. The -ñca is the enclitic conjunction ca (and) with sandhi contraction.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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