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pro- Prefix "for;" "in support of;" "toward"
From Latin pro- "for." From Proto-Italic *prō "before." From Proto-Indo-European *pro 'id.' From the verb *per- "to pass through," "to cross."
Indo-European
Italic
Oscan pru "for," Umbrian prú- 'id.'
Celtic
Old Irish ro, forms the perfective
Germanic
Gothic fra-, forms the perfective
Balto-Slavic
Old Church Slavonic pro- "through," Russian pro- 'id.,' Czech pro- 'id.,' Bulgarian pro- 'id.,' Lithuanian pra- 'id.'
Hellenic
Ancient Greek πρό (pró) "before"
Indo-Iranian
Sanskrit prá "before," Avestan fra- 'id.'