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

The UK benchmark peaked briefly at almost 183p per therm on Thursday before easing back to 154.8p, an 11.3% increase from Wednesday's level.

From BBC • Mar. 19, 2026

Oil reached $116.78 a barrel on 9 March, while UK gas reached 162.55p a therm on 3 March.

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