Ti·ti·ca·ca 
(tĭt′ĭ-käkə, tē′tē-käkä), Lake
(tĭt′ĭ-käkə, tē′tē-käkä), Lake A freshwater lake of South America in the Andes on the Bolivia-Peru border. Lying at an elevation of 3810 m (12,500 ft), it is the highest lake in the world to be navigable by large vessels.