thermal

adjective
ther·​mal | \ ˈthər-məl How to pronounce thermal (audio) \

Definition of thermal

 (Entry 1 of 2)

1a : of, relating to, or caused by heat thermal stress thermal insulation
b : being or involving a state of matter dependent upon temperature thermal conductivity thermal agitation of molecular structure
c : having low energies of the order of those due to thermal agitation thermal neutrons
2 : designed (as with insulating air spaces) to prevent the dissipation of body heat thermal underwear
3 [Latin thermae public baths, from Greek thermai, plural of thermē] : of, relating to, or marked by the presence of hot springs thermal waters

thermal

noun

Definition of thermal (Entry 2 of 2)

: a rising body of warm air

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Other Words from thermal

Adjective

thermally \ ˈthər-​mə-​lē How to pronounce thermal (audio) \ adverb

Did you know?

In days gone by, much of the male population of the northern states in the cold months would wear a garment of thermal underwear covering the entire body, called a union suit. Union suits kept sodbusters, cowboys, and townsfolk alike not only warm but also itchy and a little on the smelly side (back when bathing once a week was considered the height of cleanliness). Thermal imaging is photography that captures "heat pictures"--rather than ordinary light pictures--of objects. And thermal pollution occurs when industrial water use ends up warming a river in a damaging way. Small-plane pilots use thermal as a noun for a warm updraft, often over a plowed field or desert, that lifts their wings, just as it enables hawks to soar upward without moving their wings.

Examples of thermal in a Sentence

Recent Examples on the Web: Adjective The founder of Adani Group controls companies ranging from ports and aerospace to thermal energy and coal. Diksha Madhok, CNN, 5 July 2021 Heat pumps run off electricity, using the refrigeration cycle to heat and cool by transferring thermal energy from a cooler space to a warmer space. BostonGlobe.com, 20 June 2021 Neither agency offered reasons for the growth in renewables, but analysts have cited renewables’ zero marginal cost: every additional unit of thermal energy requires the producer to buy additional fuel. Jeff Mcmahon, Forbes, 18 June 2021 Smith disagrees, saying ITER will mark the first time a fusion device will generate more thermal energy than the energy needed to heat the plasma — and do it over long periods of time. Rob Nikolewski, San Diego Union-Tribune, 15 June 2021 And because the bot uses thermal energy to eradicate weeds, rather than a physical intervention like tilling, the machine doesn't disturb the soil below. Caroline Delbert, Popular Mechanics, 6 May 2021 Planets with relatively cold cores (compared to stars) should be better at trapping dark matter, because a hot core could give dark matter enough thermal energy to escape. Max G. Levy, Wired, 3 May 2021 Officials at the Electric Reliability Council of Texas told reporters this week the amount of thermal power offline because of the storm was about double the amount of renewable sources. Rick Rouan, USA TODAY, 18 Feb. 2021 The faster a planet loses its internal heat—which comes from its initial fiery formation, as well as thermal energy from radioactive decay—the sooner the planet’s geologic activity will cease. Robin George Andrews, Scientific American, 20 Jan. 2021 Recent Examples on the Web: Noun With lockdowns lifting, many employers plan to use systems, including fever-detecting thermal cameras, mask-checking systems and corporate contact-tracing devices, to help prevent new Covid-19 outbreaks. Stephanie Bodoni, Bloomberg.com, 1 June 2020 Fever-checking thermal cameras are also starting to become ubiquitous. Helene Fouquet, Fortune, 23 May 2020 Fever-checking thermal cameras are also starting to become ubiquitous. Helene Fouquet, Fortune, 23 May 2020 Fever-checking thermal cameras are also starting to become ubiquitous. Helene Fouquet, Bloomberg.com, 20 May 2020 Some airports, such as London Heathrow, Puerto Rico's San Juan airport, and Paine Field—a secondary airport in Seattle—are using thermal cameras to scan crowds for feverish temperatures. Jessica Puckett, Condé Nast Traveler, 12 May 2020 In Florida's Palm Beach County, Dahua thermal cameras sold by RedSpeed and installed last month scan everyone who enters the county jail and courthouse, while a deputy with a laptop reviews people's temperatures from nearby. Drew Harwell, Anchorage Daily News, 11 May 2020 In Midtown Manhattan, thermal cameras will measure body temperatures as employees file into a 32-story office tower at Rockefeller Center. Konrad Putzier And Chip Cutter, WSJ, 5 May 2020 More than 1,500 thermal cameras were shipped to Amazon warehouses by China’s Zhejiang Dahua Technology, and at least 500 of the cameras are being sold within the U.S., Reuters reported Wednesday citing three sources. Spencer Neale, Washington Examiner, 29 Apr. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'thermal.' 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 thermal

Adjective

1742, in the meaning defined at sense 3

Noun

1933, in the meaning defined above

History and Etymology for thermal

Adjective

Greek thermē

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Time Traveler for thermal

Time Traveler

The first known use of thermal was in 1742

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Dictionary Entries Near thermal

Thermaïkós Kólpos

thermal

thermal agitation

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Statistics for thermal

Last Updated

25 Jul 2021

Cite this Entry

“Thermal.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thermal. Accessed 31 Jul. 2021.

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More Definitions for thermal

thermal

adjective

English Language Learners Definition of thermal

 (Entry 1 of 2)

: of, relating to, or caused by heat
: designed to keep you warm by preventing heat from leaving your body
: having hot water flowing out of the ground

thermal

noun

English Language Learners Definition of thermal (Entry 2 of 2)

: a rising current of warm air that is produced when the sun heats an area of the ground
British : thermal clothing or underwear

thermal

adjective
ther·​mal | \ ˈthər-məl How to pronounce thermal (audio) \

Kids Definition of thermal

: of, relating to, or caused by heat thermal insulation

thermal

adjective
ther·​mal | \ ˈthər-məl How to pronounce thermal (audio) \

Medical Definition of thermal

1 : of, relating to, or caused by heat tactile and thermal senses
2 : being or involving a state of matter dependent upon temperature thermal agitation of molecular structure

Other Words from thermal

thermally \ -​mə-​lē How to pronounce thermal (audio) \ adverb

More from Merriam-Webster on thermal

Nglish: Translation of thermal for Spanish Speakers

Britannica English: Translation of thermal for Arabic Speakers

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