Republic of Costa Rica re·pub·li·cofcostarica uncommon noun 1. a republic in Central America; one of the most politically stable countries in Latin America SynonymsCosta RicaRepublic of Costa Rica Related words Broader terms Central American country Parts Central AmericaOrganization of American States Part of San JoseCosta Rican WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.