Brazil , Port. Brasil, officially Federative Republic of Brazil, republic (2005 est. pop. 186,113,000), 3,286,470 sq mi (8,511,965 sq km), E South America. By far the largest of the Latin American countries, Brazil occupies nearly half the continent of South America, stretching from the Guiana Highlands in the north, where it borders Venezuela, Guyana, Suriname, and French Guiana, to the plains of Uruguay, Paraguay, and Argentina in the south. In the west it spreads to the equatorial rain ...