ind.
Analysis. Compound of ud + ā + hu (interrogative particle). The prefix ud- (up, out) combines with ā- (toward) to give directional force to the question, while hu is an old interrogative marker; the whole construction marks the second (or alternative) part of a disjunctive question.
Etymology. ud- (up, out; cognate with English 'out', German 'aus') + ā- (toward; Sanskrit ā-) + hu- (interrogative particle, related to Sanskrit katham 'how' and Latin quī 'who'). The sense evolved from a literal 'up toward?' (a directional interrogative) to the conjunction 'or' in alternatives.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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