Didymus Chalcenterus (dĭdˈĭməs kălsĕnˈtərəs) [key], fl. 1st cent. B.C., Hellenistic Greek grammarian and expositor. Famous for his prodigious literary output, he supposedly produced over 3,500 works. He collated much of the work of the Alexandrian critics, and though only fragments of his own work are extant, he is probably the source of many surviving classical commentaries.