3rd person singular optative (conditional)
Analysis. The optative expresses wish, condition, or possibility. Here the auxiliary siyaṁ substitutes for the regular optative bhaveyyaṁ in Middle Indic sound-change, maintaining the same modal force.
Etymology. From √bhū (Sanskrit bhavati, Latin fui "I was", English be). The optative stem *bhuya- was remodeled through Middle Indic sound-shifts to siya-.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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