успешный

From LSJ

πολλῶν ὁ καιρὸς γίγνεται διδάσκαλος → the critical moment will turn out to be the teacher of many things

Source

Russian > Greek

χρηστός, οὔριος, εὔροος, ἐΰρροος, εὔρους, εὐτυχής