Cistern

Waterproof receptacle for holding liquids, usually water

A cistern (from Middle English cisterne; from Latin cisterna, from cista 'box'; from Ancient Greek κίστη (kístē) 'basket') is a waterproof receptacle for holding liquids, usually water. Cisterns are often built to catch and store rainwater. To prevent leakage, the interior of the cistern is often lined with hydraulic plaster.

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