therm

¹ American  

[thurm] / θɜrm /

Or therme

noun

Physics.

1. any of several units of heat, as one equivalent to 1000 large calories or 100,000 British thermal units.

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therm- ² American  

1. variant of thermo- before a vowel.

   thermesthesia.

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-therm ³ American  

1. variant of thermo- as final element in compound words.

   isotherm.

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therm. ⁴ American  

abbreviation

1. thermometer.

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therm British  

/ θɜːm /

noun

1. a unit of heat equal to 100 000 British thermal units. One therm is equal to 1.055 056 × 10 ⁸ joules

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Etymology

Origin of therm

First recorded in 1885–90, therm is from the Greek word thérmē heat

Example Sentences

It closed at 138p a therm, still over a fifth higher than Monday's price, before falling to 127p on Wednesday.

From BBC • Mar. 5, 2026

British wholesale gas prices have fallen from a peak of 640p per year in August 2022, to around 70p per therm.

From BBC • May 20, 2023

British gas for immediate delivery was up 85 pence to 450 pence per therm at 0940 GMT, while the day-ahead contract rose 119 pence to 480 p/therm.

From Reuters • Aug. 22, 2022

British gas for next-day delivery has jumped 40% to 280p per therm.

From The Guardian • Feb. 24, 2022

Joule's Equivalent—J.—is the amount of energy equivalent to a therm or calorie, the metric unit of heat.

From The Story of Electricity by Munro, John