πρωταγωνιστής

A. one who plays the first part, chief actor, ib.816f; π. τοῦ δράματος Luc. Cal. 7: metaph., [ὁ Αἰσχύλος] τὸν λόγον π. παρεσκεύασεν Arist. Po. 1449a18: generally, leader, π. τῆς ὑπηρεσίας Clearch. 25; τοῖς μαθηματικοῖς, of king Antiochus, Ps.-Diocl. ap. Paul.Aeg. 1.100: expl. of πρόμαχος, EM 612.51.