| Cistern 1. (n.) An artificial reservoir or tank for holding water, beer, or other liquids. 2. (n.) A natural reservoir; a hollow place containing water. Thesaurus Entries artificial lake, bayou lake, dam, dead water, dike, etang, farm pond, fishpond, freshwater lake, glacial lake, inland sea, lagoon, laguna, lake, lakelet, landlocked water, linn, loch, lough, mere, millpond, millpool, nyanza, oxbow lake, plash, pond, pondlet, pool, puddle, reservoir, salina, salt pond, stagnant water, standing water, still water, sump, tank, tarn, tidal pond, volcanic lake, water hole, water pocket, well |