a city in western Brazil and the administrative center of the Mato Grosso state. Population, 100,900 (1970). Cuiabá is a port on the Cuiabá River (a tributary of the Paraguay) and a highway junction; it has an airport. The city is one of the centers of an underdeveloped region, whose economy is based on gold and diamond mining, lumber industries, hunting, fishing, and subsistence agriculture. The major industries are food-processing, woodworking, and the production of building materials. Cuiabá was founded in the 18th century.