The largest lake of Central America, in southwest Nicaragua. The freshwater lake contains fish, such as tuna and sharks, usually found only in salt water because it was part of the Caribbean Sea until land masses rose around it in prehistoric times. a country in Central America between the Caribbean Sea and the Pacific Ocean, and south of Honduras and north of Costa Rica. Population: 4,918,000 (2001). Capital: Managua. Its main products are coffee, cotton, and sugar. In the 1980s there was a civil war. officially Republic of Nicaragua Country, Central America