accusative pronoun taṁ (that) + nominative pronoun ahaṁ (I); elision and contraction (ty- from taṁ before initial a- of ahaṁ, dropping intermediate vowel)
Analysis. Contraction of taṁ (accusative of tad, that) + ahaṁ (I); the accusative taṁ loses its final nasal and fuses with the initial vowel of ahaṁ, creating ty- as the fused onset. This construction is rare in canonical Pali but occurs in metrical contexts where speakers adopt an archaic or poetic register, or in certain grammatically anomalous utterances.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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