sandhi contraction: etad + ahosi
Analysis. etad (neuter singular demonstrative pronoun 'this') + ahosi (3rd person singular imperfect of atthi 'was, became'); the contraction etad + ahosi > etadahosi represents the fusion of a pronoun object and imperfect verb, common in narrative prose where an idea or thought suddenly arises to a character.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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