thermal

adjective ther·mal \ ˈthər-məl \

Updated on: 14 May 2018

Definition of thermal

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

[Latin thermae public baths, from Greek thermai, plural of thermē]

: of, relating to, or marked by the presence of hot springs

thermal waters

—

thermally

play \ˈthər-mə-lē\ adverb

See thermal defined for English-language learners

See thermal defined for kids

Recent Examples of thermal from the Web

For pumps, batteries, your own electrical supplies, water, cooling, thermal capacity — all of those things that typically tend to go into a safety analysis study.

— rachel becker, The Verge, "This nuclear power plant has been called a ‘floating Chernobyl,’ but is that just hype?," 2 May 2018
Flir hopes to produce a system that can use thermal imaging to automatically spot problems up ahead, alerting the driver or even applying the brakes as needed.

— alex davies, WIRED, "Heat-Seeking Cameras Could Help Keep Self-Driving Cars Safe," 21 Apr. 2018
The Cook County medical examiner’s office said Braschko died from thermal injuries caused by careless use of smoking materials, and her death was determined to be an accident.

— chicago tribune staff, chicagotribune.com, "Woman dies following fire at Rolling Meadows home," 17 Apr. 2018
Using breathing devices and a thermal-imaging camera, firefighters were able to find the woman and pull her out, Van Hook said.

— chris mccrory, azcentral, "FD: Woman in 'extremely' critical condition after being trapped in flaming Phoenix home," 15 Apr. 2018
The robots gets direction from thermal imaging and camera vision to get direction on when to flip the burger and eventually remove it.

— jefferson graham, USA TODAY, "Flippy the robot is now cooking up burgers near L.A., and that's just the start," 5 Mar. 2018
Nuclear thermal propulsion has a number of advantages over current chemical and electric propulsion systems.

— jay bennett, Popular Mechanics, "NASA's Nuclear Thermal Engine Is a Blast From the Cold War Past," 21 Feb. 2018
Gucci Westman: Avène thermal water spray, pointy cotton swabs, and black makeup wipes from Japan.

— ying chu, Glamour, "Makeup Artist Gucci Westman's New Line Is Paradise for Finicky Skin," 27 Apr. 2018
An autopsy concluded that Holmes died of smoke inhalation and thermal injuries as well as multiple stab wounds.

— greg norman, Fox News, "Pennsylvania man stabbed, burned alive in 'very violent type of homicide'," 26 Apr. 2018

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.

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.