Definition of cisterns:
(n) :
A reservoir or tank for holding water, especially for catching and holding rainwater for later use.
(n) :
In a flush toilet, the container in which the water used for flushing is held; a toilet tank.
(n) :
A shallow, typically oval, vessel made of porcelain, pottery, or glass.
(n) :
The receptacle that holds the fuel in an oil lamp.
(n) :
(biology) A cisterna.
(n) :
The vessel surrounding the condenser in a steam engine.