The Collaborative International Dictionary of English v.0.48:
Issus \Issus\ prop. n. A battle (333 BC) in which Alexander the Great defeated the Persians under Darius III. Syn: battle of Issus. [WordNet 1.5]WordNet (r) 3.0 (2006):
Issus n 1: a battle (333 BC) in which Alexander the Great defeated the Persians under Darius III [syn: Issus, battle of Issus]