geo·​ther·​mal | \ ˌjē-ō-ˈthər-məl How to pronounce geothermal (audio) \

Definition of geothermal

: of, relating to, or utilizing the heat of the earth's interior also : produced or permeated by such heat geothermal steam geothermal regions

Other Words from geothermal

geothermally \ ˌjē-​ō-​ˈthər-​mə-​lē How to pronounce geothermal (audio) \ adverb

Did you know?

Geothermal comes partly from the Greek thermos, "hot". Most geothermal electricity is provided by power plants situated in areas where there is significant activity of the Earth's great tectonic plates—often the same areas where volcanoes are found. But hot water from deep underground may be used by cities far from volcanoes to heat buildings or sidewalks. And a newer source of geothermal energy relies on a less dramatic kind of heat: Individual homeowners can now install heat pumps that take advantage of the 50°-60° temperature of the soil near the surface to provide heating in cold weather (and air-conditioning in the warm months). These very small-scale geothermal systems may eventually supply more useful energy than the large power plants.

Examples of geothermal in a Sentence

Recent Examples on the Web In 2020, renewables – including wind, hydroelectric, solar, biomass, and geothermal energy – became the second most prominent electric-power source in the United States after natural gas, according to the Energy Information Administration. Stephanie Hanes, The Christian Science Monitor, 30 June 2022 In other instances, manufacturers with large campuses are even investing in on-site generation, using solar panels, wind turbines, and geothermal pumps to power their facilities. Vincent Rutgers, Forbes, 1 Oct. 2021 For example, the tax code gives offshore wind investments a 30% investment tax credit, while investments in geothermal heat pumps receive a credit of only 10%. WSJ, 12 July 2021 As the resort's name suggests, its primary draw is the mineral-rich geothermal hot springs. Michael Salerno, The Arizona Republic, 14 July 2022 Set among woodland just 5 minutes’ drive from Akureyri, the naturally-heated geothermal waters were originally a problem for construction of a tunnel connecting Akureyri and Húsavik. David Nikel, Forbes, 11 July 2022 The process would be paired with geothermal production of electricity. Eric D. Lawrence, Detroit Free Press, 2 June 2022 The county’s geothermal electricity means their local carbon costs are effectively $0. Robinson Meyer, The Atlantic, 25 May 2022 Yellowstone's Super Volcano and geothermal features 27. Fox News, 21 May 2022 See More

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

First Known Use of geothermal

1875, in the meaning defined above

History and Etymology for geothermal

geo- + thermal entry 1

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Time Traveler for geothermal

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The first known use of geothermal was in 1875

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Dictionary Entries Near geothermal



geothermal gradient

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Statistics for geothermal

Last Updated

4 Aug 2022

Cite this Entry

“Geothermal.” Dictionary, Merriam-Webster, Accessed 15 Aug. 2022.

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