\ ˈthərm How to pronounce therm (audio) \

Definition of therm

 (Entry 1 of 3)

: a unit for quantity of heat that equals 100,000 British thermal units
variants: or thermo-

Definition of therm- (Entry 2 of 3)

1 : heat thermostat
2 : thermoelectric thermopile

Definition of -therm (Entry 3 of 3)

: animal having a (specified) body temperature ectotherm

Examples of therm in a Sentence

Recent Examples on the Web: Noun Typical residential customers of NW Natural using 54 therms per month will see their bill increase by $2.31, or 4.4%, from $52.43 to $54.74. USA TODAY, "Lighthouse in peril, Wizard Rock, cable a la carte: News from around our 50 states," 4 Nov. 2019 The average residential customer in Denver used about 6,100 kilowatt hours and 724 therms in 2018, according to Xcel Energy data. Andrew Kenney, The Denver Post, "Energy tax on Denver homes and businesses approved for 2020 ballot," 4 Sep. 2019 SUBSCRIBE TODAY Typical residential costumers are expected to see $7.04 decrease in their monthly power bills and a $0.015 drop per therm in their gas bills, the PUC said. Michael Katz, idahostatesman, "Good news, Treasure Valley utility customers: Your bills will go down. Here's why.," 15 June 2018 The commission also expects that by the first year of implementation, statewide annual electricity consumption will be cut by about 653 gigawatt-hours and natural gas consumption reduced by 9.8 million therms. Rob Nikolewski,, "California becomes first state requiring all new homes be built with solar," 9 May 2018 Aliyev won his fourth therm in an election boycotted by major opposition parties, who accused him of authoritarianism and suppressing political dissent. Collin Eaton, Houston Chronicle, "Oil and gas cybersecurity projects went "to the bottom of the pile" in energy slump," 12 Apr. 2018 Gas Inflation Gas for same-day delivery in the U.K. more than doubled to as high as 190 pence a therm ($26.20 a million British thermal units), broker data compiled by Bloomberg show. Anna Shiryaevskaya,, "London Covered in Snow as Cold Snap Makes Energy Markets Shiver," 28 Feb. 2018 The energy-saving steps taken by GKN have saved the equivalent of more than 1.5 million kilowatt hours of electricity and more than 30 thousand therms of natural gas, the release said. Tyler Langan, Milwaukee Journal Sentinel, "GKN Sinter Metals in Germantown gets $145,000 for taking energy-efficiency measures," 14 Feb. 2018 The utility estimates a typical residential customer using 500 kilowatt-hours of electricity each month would see an increase of $6.13 and a typical customer using 25 therms of natural gas would spend $7.57 more on a monthly bill. Rob Nikolewski,, "SDG&E wants to raise rates 11%, starting in two years," 6 Oct. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'therm.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of therm


1888, in the meaning defined above

History and Etymology for therm


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

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Time Traveler for therm

Time Traveler

The first known use of therm was in 1888

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Statistics for therm

Cite this Entry

“Therm.” Dictionary, Merriam-Webster, Accessed 24 Oct. 2020.

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More Definitions for therm


\ ˈthərm How to pronounce therm (audio) \

Medical Definition of therm

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

More from Merriam-Webster on therm Encyclopedia article about therm

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