A cistern is an underground tank that holds water. A long time ago, cistern water was used for drinking, but nowadays developed parts of the world mainly use it for watering plants and flushing toilets.

The oldest cisterns that we know of were built in the Middle East about 12,000 years ago, which is around when farming was invented. That's no coincidence. It would be tough to collect enough water to grow barley and wheat without storing the water in something, especially in a place as dry as the Middle East.

Definitions of cistern
  1. noun
    a sac or cavity containing fluid especially lymph or cerebrospinal fluid
    synonyms: cisterna
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    type of:
    a structure resembling a bag in an animal
  2. noun
    an artificial reservoir for storing liquids; especially an underground tank for storing rainwater
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    cesspit, cesspool, sink, sump
    a covered cistern; waste water and sewage flow into it
    rain barrel
    a barrel used as a cistern to hold rainwater
    type of:
    an excavation that is (usually) filled with water
    tank used for collecting and storing a liquid (as water or oil)
  3. noun
    a tank that holds the water used to flush a toilet
    synonyms: water tank
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    type of:
    storage tank, tank
    a large (usually metallic) vessel for holding gases or liquids
Word Family

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