thermostat

American  

[thur-muh-stat] / ˈθɜr məˌstæt /

noun

1. 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.

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verb (used with object)

thermostatted, thermostated, thermostatting, thermostating

1. to equip or control with a thermostat.

thermostat British  

/ ˈθɜːməˌstæt /

noun

1. 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

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

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thermostat Scientific  

/ thûr′mə-stăt′ /

1. A device that automatically controls heating or cooling equipment in such a way as to maintain a temperature at a constant level or within a specified range, generally using a thermometer capable of triggering electrical switches that activate or deactivate the equipment.

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thermostat Cultural  

1. A device that monitors and automatically responds to changes in temperature and activates switches controlling devices such as furnaces or air conditioners.

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Other Word Forms

• thermostatic adjective
• thermostatically adverb

Etymology

Origin of thermostat

First recorded in 1825–35; thermo- + -stat

Example Sentences

It is often called a silent killer because most heat deaths occur gradually as high temperatures and other environmental factors work together to undermine the body's internal thermostat.

From Barron's • Jan. 26, 2026

The detachable thermostat plugs into the blanket and connects to an outlet up to 70 inches away.

From The Wall Street Journal • Jan. 23, 2026

“That doesn’t look like it’ll go away anytime soon. People are going to be heavy on the thermostat for a good two weeks,” he said.

From MarketWatch • Jan. 22, 2026

If weight drops below this "set point", hunger rises and metabolism slows, just as a thermostat turns up the heat when it's too cold, according to that theory.

From BBC • Jan. 4, 2026

A thermostat clicked off and a heater stopped humming.

From "Black Swan Green" by David Mitchell

Related Words

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