masc nom sg of attadutiya (adj)
Analysis. atta (self, reflexive pronoun) + dutiya (second, ordinal number); the compound expresses 'having oneself as a second,' i.e. accompanied by one other person.
Etymology. atta is the reflexive pronoun from the root √as (to be); dutiya is the ordinal form from dvi (two), cognate with Sanskrit dvi, Greek dyo, Latin duo, English two. The compound employs the common Pali pattern of expressing accompaniment through 'being accompanied by another self' or second person.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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