It starts in the southern Himalayas, dissects the land from north to south and empties through a nine armed delta into the Indian Ocean. In colonial times, before railways and car roads the river was known as the "Road to Mandalay".
Its name is believed to derive from the Sanskrit term "airavati", meaning "elephant river".
The Irrawaddy gives its name to a dolphin, the Irrawaddy Dolphin Orcaella brevistosus, which is found in the river. Though sometimes called the Irrawaddy River Dolphin, it is not a true river dolphin, since it is also found at sea.