(Spanish. after Mayan tzonet or dzonot.) 1. Steep-walled natural well that extends below the water table; generally caused by collapse of a cave roof. Term used only for features in Yucatan [10]. 2. Steep or vertical sided collapse doline floored by a lake whose surface is at the regional water table. The term originates from the many cenotes in the low karst plateau of Mexico's Yucatan, but has been applied to flooded dolines in Florida and elsewhere. Probably the most famous cenote is the sacred well of Chichen Itza, Yucatan; it has vertical sides and is 60m in diameter, 30m deep and half full of water [9]. Synonyms: (French.) cenote; (German.) cenote; (Greek.) voulismeno speleven. See also jama; natural well.