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o- (1), op- (Prefix) "power to help"
Not productive in Spanish. From Latin ops 'id.' From Proto-Italic *opi- 'id.' From Proto-Indo-European *h3ep-i̯- "force." From *h3ep- "to work," "to force."
Indo-European
Hellenic
Ancient Greek ὄμπνη (ómpen) "corn"
Indo-Iranian
Sanskrit ápnas- "property," Young Avestan -haṇt- "rich"