Body of water and Cistern

Body of water noun - The part of the earth's surface covered with water (such as a river or lake or ocean).

Cistern and body of water are semantically related in reservoir topic. In some cases you can use "Cistern" instead a noun phrase "Body of water", when it comes to topics like pool.

Cistern noun - A sac or cavity containing fluid especially lymph or cerebrospinal fluid.

Body of water and cistern are semantically related in reservoir topic. You can use "Body of water" instead a noun "Cistern", if it concerns topics such as pool.