sandhi contraction
Analysis. ayaṃ 'this' + āyasmā 'venerable one' (honorific form of address for monks). A nominative singular demonstrative pronoun followed by an honorific title, contracted in speech; the initial ā- of āyasmā assimilates after the nasal ending of ayaṃ.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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