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

When trading began on Thursday morning, UK gas prices briefly surged over 30%, and are currently up about 22% at 170p per therm.

From BBC • Mar. 19, 2026

The benchmark UK gas price also jumped by 6% to 143.53p a therm before falling back below the 140p mark.

From BBC • Mar. 18, 2026

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

It is currently 8.3% higher at 426.9p per therm, not far from the all-time high of around 450p in December.

From The Guardian • Mar. 3, 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