Araguay (ä-rä-gwī), an affluent of the Tocantins, an important river of central and northern Brazil, which reaches the Atlantic through the Para River. Total length, including the Tocantins and the Para, 1,900 miles. In the lower reaches of the river, some 200 miles above Para, the navigation is much interrupted by rapids. About 500 miles from its source, the Araguay incloses the island of Santa Anna, about 210 miles long.
