Amu DaryaPronunciation: /ˌɑːmuː ˈdɑːrɪə/Definition of Amu Darya a river of central Asia, rising in the Pamirs and flowing 2,400 km (1,500 miles) into the Aral Sea. In classical times it was known as the Oxus. Amu Darya in other Oxford dictionaries Definition of Amu Darya in the US English dictionary