regenerator

Noun

 * 1) One who, or that which, regenerates.
 * 2)  A type of heat exchanger where heat from the hot fluid is intermittently stored in a thermal storage medium before it is transferred to the cold fluid.
 * 1)  A type of heat exchanger where heat from the hot fluid is intermittently stored in a thermal storage medium before it is transferred to the cold fluid.

Etymology
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