a device, including a relay actuated by thermal conduction or convection, that functions to establish and maintain a desired temperature automatically or signals a change in temperature for manual adjustment.

to equip or control with a thermostat.

a device that maintains a system at a constant temperature. It often consists of a bimetallic strip that bends as it expands and contracts with temperature, thus breaking and making contact with an electrical power supply

a similar device that actuates equipment, such as a sprinkler, when a certain temperature is reached