Clazomenae (kləzŏm`ĭnē), ancient city of W Asia Minor, 20 mi (32 km) W of present-day Izmir, Turkey. It was one of the 12 Ionian cities of Asia Minor. The city was founded on the mainland but was later moved to a small island, and Alexander the Great built a causeway to it. The town continued to flourish through the Hellenistic and Roman periods. It was the birthplace of the philosopher Anaxagoras.