Hippodamus (hĭpŏd`əməs), fl. 5th cent. B.C., Greek architect, b. Miletus. He was the first to plan cities according to geometric layouts. For Pericles he remodeled Piraeus (the port of Athens). He also planned (408) the city of Rhodes and went with the Athenian colonists to replan (c.440) the new city of Thurii in Italy. Other cities of the ancient world followed his methods.