Bolivia (bōlĭv´ēә, Span. bōlē´vyä), officially Plurinational State of Bolivia, republic (2005 est. pop. 8,858,000), 424,162 sq mi (1,098,581 sq km), W South America. One of the two inland countries of South America, Bolivia is shut in from the Pacific in the W by Chile and Peru; in the E and N it borders on Brazil, in the SE on Paraguay, and in the S on Argentina. Sucre is the constitutional capital and seat of the judiciary, but La Paz is the largest city, political and commercial focus of the nation, and the administrative capital and seat of government..