A small karst lake occupying a doline or closed depression in limestone. The term implies that the doline is at or near the ground-water table and in hydrological continuity with it, or that the base of the doline is sealed with an impermeable layer such as clay [20]. See also sinkhole pond. Synonyms: (French.) lac de doline; (German.) Dolinensee; (Greek.) limni dholina; (Italian.) lago di dolina, lago carsico; (Russian.) karstovoe ozero; (Spanish.) dolina laguna, torca laguna; (Turkish.) obruk golu; (Yugoslavian.) krsko jezero, krasko jezero.