Equatorial Guinea gĭn´ē [key], officially Republic of Equatorial Guinea, republic (2005 est. pop. 536,000), 10,830 sq mi (28,051 sq km), W central Africa. It includes the islands of Bioko (formerly Fernando Po), Annobón, Corisco, Elobey Grande, and Elobey Chico in the Gulf of Guinea, and Río Muni