1 of 3


: a unit for quantity of heat that equals 100,000 British thermal units


2 of 3

combining form

variants or thermo-
: heat
: thermoelectric


3 of 3

noun combining form

: animal having a (specified) body temperature

Examples of therm in a Sentence

Recent Examples on the Web
High usage: An additional $9 for 70 therms of gas and an additional $51 for 750 kWh of electricity. Angela Rodriguez, Sacramento Bee, 24 Jan. 2024 The commodity, or wholesale, price of natural gas reached $1.05 per therm in December 2022 and soared to $3.45 per therm one month later. Rob Nikolewski, San Diego Union-Tribune, 6 Dec. 2023 The five-year average is 31 therms in December, 44 in January, 39 in February and 35 in March. Rob Nikolewski, San Diego Union-Tribune, 26 Oct. 2023 April’s commodity price of 43 cents per therm represents a return to a more normal price range. Rob Nikolewski, San Diego Union-Tribune, 31 Mar. 2023 February prices per therm should drop 68% from January — still up from what customers paid in December 2022 and still higher than usual for February, historically, according to one SoCalGas executive, but a decline from last month’s dramatic jump in cost. Stephanie Breijo, Los Angeles Times, 26 Feb. 2023 The commodity price of natural gas plays the biggest part of the overall cost per therm that utility customers pay. San Diego Union-Tribune, 14 Dec. 2022 The March price is also 82.6 percent lower than January’s sky-high price of $3.45 per therm. San Diego Union-Tribune, 28 Feb. 2023 Mares said he got frustrated after reading the fine print of his bill, which said he was being charged $3.45 per therm (one unit of natural gas), up from 84 cents at the same time last year. Los Angeles Times, 15 Feb. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'therm.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History



Greek thermē heat, from thermos hot; akin to Latin formus warm, Sanskrit gharma heat

Combining form

Greek, from thermē

Noun combining form

Greek thermē heat

First Known Use


1888, in the meaning defined above

Time Traveler
The first known use of therm was in 1888

Dictionary Entries Near therm

Cite this Entry

“Therm.” Dictionary, Merriam-Webster, Accessed 29 May. 2024.

Medical Definition


: any of several units of quantity of heat: as
: 1000 kilogram calories
: 100,000 British thermal units

More from Merriam-Webster on therm

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