Skip to content
Science & TechnologyGreekEnglish

Thermostat

/ˈθɜːrməstæt/noun

A device that switches heating or cooling on and off to hold a set temperature.

The Greek roots

θερμός
thermós
hot, warm
+
στατός
statós
standing, held fixed

Literally: heat held standing

The story of the word

Andrew Ure patented a bimetallic heat regulator in 1830 and the name came with it: two metals bonded together, bending as they expand at different rates, breaking a circuit. Warren Johnson put one in a Milwaukee classroom in 1883 and founded a company on it. The -stat ending went on to build rheostat, gyrostat and photostat, all of them things that hold something steady.

How it travelled
Ancient Greek → scientific coinage → English
First recorded
1831

The same roots elsewhere

Other languages reached for exactly the same Greek pieces.

Same family

thermometerthermalrheostatstatic

In a sentence

Somebody had set the thermostat to 26 and then left for the weekend.

Built on the same root

More from Science & Technology