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

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Other Words from geothermal

geothermally \ ˌjē-​ō-​ˈthər-​mə-​lē How to pronounce geothermally (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

According to a press release from the British Antarctic Survey, the hot spot was originally hinted at in 2001 when low-resolution satellite data showed a geothermal anomaly at the top of the peak. Jason Daley, Smithsonian, "Rare Lava Lake Found on Top of Sub-Antarctic Volcano," 8 July 2019 About 12 miles later, at the confluence of the Roaring Fork and Colorado rivers, your ride ends in Glenwood Springs, renowned for its geothermal activity. Jeanine Barone, The Know, "Ride your bike on these Colorado railroad routes without fear of being run over by a train," 2 July 2019 Some subglacial lakes form when pressure from above or geothermal hot spots from below melt portions of the ice, others when meltwater trickles down from above through holes known as moulins to pool in hollows under the ice. NBC News, "Dozens of lakes discovered deep under the Greenland Ice Sheet," 29 June 2019 Wandering through the colorful terrain of a geothermal field is a classic Icelandic treat. Rick Steves, USA TODAY, "Geothermal baths and beyond: Rick Steves' guide to Iceland's steamiest sites," 25 June 2019 This means there are plenty of geothermal hot spots that beckon visitors to visit. Liz Carlson, Outside Online, "8 Can't-Miss New Zealand Adventures," 24 June 2019 However, geothermal reactions devoid of biology can also generate methane. Kenneth Chang,, "NASA rover on Mars detects puff of gas that hints at possibility of life," 22 June 2019 However, geothermal reactions devoid of biology can also generate methane. New York Times, "NASA Rover on Mars Detects Puff of Gas That Hints at Possibility of Life," 22 June 2019 Because of high snow above 7,500 feet, camps at Summit Lake, Juniper Lake, and the trailhead for Bumpass Hell geothermal area, will not open until well into July, and perhaps later. Tom Stienstra,, "Snow thaw means Sierra campgrounds finally opening for summer," 20 June 2019

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.

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First Known Use of geothermal

1875, in the meaning defined above

History and Etymology for geothermal

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Statistics for geothermal

Last Updated

11 Jul 2019

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Time Traveler for geothermal

The first known use of geothermal was in 1875

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English Language Learners Definition of geothermal

: of, relating to, or using the natural heat produced inside the Earth also : produced by such heat

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