thermal

1 of 2

adjective

ther·​mal ˈthər-məl How to pronounce thermal (audio)
1
a
: 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
thermally adverb

thermal

2 of 2

noun

: a rising body of warm air

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
Guests are scrubbed down with thermal salt from Sárvár, slicked with lavender and almond oil, packed with a mud mask from Lake Hévíz that draws out impurities, and enveloped in a shimmering wrap that conjures discos, all while the therapist performs a vigorous Hungarian face and body massage. Alia Akkam, Condé Nast Traveler, 14 Mar. 2024 Wear a visible hat, take a tow float and consider a thermal wet suit for buoyancy. Sandee Lamotte, CNN, 14 Mar. 2024 Mulch can suppress weed growth and provide thermal insulation, keeping the root zone cooler in summer and warmer (and more consistent) in winter. Paul Cappiello, The Courier-Journal, 8 Mar. 2024 This property, tucked between the otherworldly cliffs along the Ojo Caliente River, boasts one of the country's only thermal springs with four healing minerals: lithia, soda, arsenic, and iron. Stephanie Vermillion, Travel + Leisure, 7 Mar. 2024 Without ice, the lakes' upper levels will likely warm even more quickly than usual, contributing to thermal stratification, in which layers of colder and warmer water form. Todd Richmond, Quartz, 7 Mar. 2024 Test shows explosive power of a lithium-ion battery thermal runaway 01:31 Climate can also affect battery operation. Wesley Chang, CBS News, 5 Mar. 2024 La Roche-Posay and Avène, two of the leading labels stocking the French pharmacy, are powered by the mineral-rich waters from the country’s thermal springs, which were discovered centuries ago to treat medical conditions like eczema, psoriasis, and rosacea. Kiana Murden, Vogue, 5 Mar. 2024 Thanks to the ceramic’s extremely high thermal conductivity, the antenna array in the melting head assists in both directing the radar signals and maintaining the probe’s ability to rapidly melt through the ice. IEEE Spectrum, 4 Mar. 2024
Noun
The music, too, is idiosyncratic: For 60 minutes, plainsong, gospel, electronica, soul and the New Orleans funk of Christian’s upbringing layer into each other like atmospheric thermals. Jesse Green, New York Times, 19 Jan. 2024 Military officials searched the river with lights, thermals and night-vision goggles but did not see any other migrants trying to cross or in distress, the statement said. Alexandra E. Petri, Los Angeles Times, 17 Jan. 2024 Though thermals, thick sweaters and puffy coats make sense on icy streets, enter a packed subway, stuffy restaurant or inferno-like office and cue the perspiration. Ashley Ogawa Clarke, WSJ, 14 Dec. 2023 Linus Tech Tips' teardown goes a bit deeper into the thermals and noise suppression of the new model. Kevin Purdy, Ars Technica, 7 Nov. 2023 And boy, does that legacy continue with these thermals. Todd Plummer, Robb Report, 25 Oct. 2023 Don’t make the mistake of thinking the thermals of today are the saggy, yellowing styles of yesteryear. Todd Plummer, Robb Report, 25 Oct. 2023 The seven-mile round-trip hike from the visitor center to Hanging Rock visits Great Bear Mound (the largest effigy, at 138 feet long), skirts tallgrass prairie, and overlooks the river from 400-foot cliffs, where hawks and eagles cruise the thermals. The Editors, Outside Online, 15 Apr. 2019 Like many sedans today, the Eagle lifts off on thermals of Audi-like ideas. Larry Griffin, Car and Driver, 11 Apr. 2023

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

Word History

Etymology

Adjective

Greek thermē

First Known Use

Adjective

1742, in the meaning defined at sense 3

Noun

1933, in the meaning defined above

Time Traveler
The first known use of thermal was in 1742

Dictionary Entries Near thermal

Cite this Entry

“Thermal.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thermal. Accessed 29 Mar. 2024.

Kids Definition

thermal

1 of 2 adjective
ther·​mal ˈthər-məl How to pronounce thermal (audio)
1
: of or relating to a hot spring
thermal springs
2
: of, relating to, caused by, or saving heat
thermal energy
thermal underwear
thermally adverb

thermal

2 of 2 noun
: a rising body of warm air

Medical Definition

thermal

adjective
ther·​mal ˈthər-məl How to pronounce thermal (audio)
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
thermally adverb

More from Merriam-Webster on thermal

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