thermostat

A device, as in a home heating system, a refrigerator, or an air conditioner, that automatically responds to temperature changes and activates switches controlling the equipment.

An automatic instrument or apparatus for regulating temperature.

A device which automatically regulates temperature, or provides a signal used by another device to regulate temperature. The temperature-sensitive signal may be electronic, as that produced by a thermocouple. The signal may also be caused mechanically, as by the unequal expansion of different metals, liquids, or gases by heat, which can then cause the opening or closing of the damper of a stove, or the like, as the heat becomes greater or less than is desired.

a device that automatically responds to changes in temperature by activating a heating or cooling system to maintain the temperature at a desired setting

a regulator for automatically regulating temperature by starting or stopping the supply of heat

control the temperature with a thermostat