Cay Sal, [Span.=salt key], uninhabited islet, Bahama Isls., on SW fringe of Cay Sal Bank, on 45 mi/72 kmwide Nicholas Channel, separating the bank from Cuba, and 100 mi/161 km SE of Key West, Fla. Belongs with Cay Lobos (200 mi/322 km ESE) to Cay Lobos dist.