Etymology tree Proto-Indo-European *sokʷós Ancient Greek ὀπός (opós) Proto-Indo-European *-yósder. Ancient Greek -ῐος (-ĭos)? Ancient Greek -ῐον (-ĭon) Ancient Greek ὄπιον (ópion)bor. Latin opiumbor. ▲ Ancient Greek ὄπιον (ópion)bor. English opium Borrowed from Latin opium and Ancient Greek ὄπιον (ópion), from ὀπός (opós, “juice of a plant”), from Proto-Indo-European *sokʷós (“juice, resin”).