Anaxagoras Syllabification: (An·ax·ag·o·ras)Pronunciation: /ˌanəkˈsagərəs, ˌanak-/Definition of Anaxagoras (circa 500-circa 428 bc), Greek philosopher. He believed that all matter was infinitely divisible and motionless until animated by mind (nous). Anaxagoras in other Oxford dictionaries Definition of Anaxagoras in the British & World English dictionary