What is "amphipole"

Amphipoles, in antiquity, were archons, or chief magistrates, of the city of Syracuse. They were first established by Timoleon, after his expulsion of Dionysius the Elder, tyrant of Syracuse. They governed Syracuse for a space of three hundred years, and Diodorus Siculus assures us they subsisted even in his time (c. 90 BC to c. 30 BC).