nominative singular pronoun, first person (esā is a feminine demonstrative pronoun, haṁ an emphatic particle; the phrase is a contraction or colloquial fusion)
Analysis. esā (feminine demonstrative 'this') + haṁ (nominative of ahaṁ 'I', with sandhi fusion). The construction emphasizes the speaker's identity or presence in first-person declarations, common in Pali poetry and direct speech.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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