Carnot\'s cycle
Car`not's" cy"cle\ [After N. L. S. Carnot, French physicist.] (Thermodynamics) An ideal heat-engine cycle in which the working fluid goes through the following four successive operations: (1) Isothermal expansion to a desired point; (2) adiabatic expansion to a desired point; (3) isothermal compression to such a point that (4) adiabatic compression brings it back to its initial state.