ther·​mo·​nu·​cle·​ar | \ ˌthər-mō-ˈnü-klē-ər How to pronounce thermonuclear (audio) , -ˈnyü-, nonstandard -ˈn(y)ü-kyə-lər How to pronounce thermonuclear (audio) \

Definition of thermonuclear

1 : of, relating to, or employing transformations in the nuclei of atoms of low atomic weight (such as hydrogen) that require a very high temperature for their inception (as in the hydrogen bomb or in the sun) thermonuclear reaction thermonuclear weapon
2 : of, utilizing, or relating to a thermonuclear bomb thermonuclear war a thermonuclear attack

Examples of thermonuclear in a Sentence

Hydrogen bombs are thermonuclear weapons.
Recent Examples on the Web During the Cold War, the U.S., even with NATO, didn’t have primacy over the Soviet Union and Warsaw Pact for one reason: The Soviets saw a war as a fight to the finish in which nuclear and thermonuclear weapons would be used. WSJ, "The U.S. Needs Smarter Policies for Defense," 29 May 2020 Many are the remains of massive stars that collapsed after burning through their thermonuclear trust funds. Dennis Overbye, New York Times, "Deep in the Cosmic Forest, a Black Hole Goldilocks Might Like," 6 May 2020 In one unsettling plot twist, a package containing a small thermonuclear device is slipped into an order of emergency food supplies. Adrian Chen, New York Times, "Hideo Kojima’s Strange, Unforgettable Video-Game Worlds," 3 Mar. 2020 The new estimate is dramatically bigger than previous North Korean nuclear tests, lending credence to claims that a thermonuclear device was tested. Kyle Mizokami, Popular Mechanics, "North Korea's Latest Nuclear Test Was More Powerful Than We Thought," 5 June 2019 Pandemics have become a threat on the scale of thermonuclear war. Mark Olshaker, Fortune, "To fight tomorrow’s pandemic, we need to think like the military today," 20 Apr. 2020 Created by David Lynch and Mark Frost, the feature-length pilot set off a thermonuclear explosion of artistic influence, immediately expanding the boundaries of TV drama. Darren Franich,, "A Twin Peaks Podcast celebrates 30 years of fantastic trees," 7 Apr. 2020 Like our own sun, Betelgeuse transfers its thermonuclear energy by convection from the center, where it is generated, to its surface. Dennis Overbye, New York Times, "The Further Adventures of Betelgeuse, the Fainting Star," 14 Feb. 2020 Eleven months earlier, as the Cold War escalated, the U.S. detonated a bomb dubbed Castle Bravo in the first of a series of thermonuclear tests at Bikini Atoll, Marshall Islands. Nataly Keomoungkhoun, Dallas News, "Does Dallas still have any of its Cold War-era nuclear bomb fallout shelters? Curious Texas investigates," 12 Feb. 2020

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

1938, in the meaning defined at sense 1

History and Etymology for thermonuclear

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Time Traveler for thermonuclear

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The first known use of thermonuclear was in 1938

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Cite this Entry

“Thermonuclear.” Dictionary, Merriam-Webster, Accessed 24 Nov. 2020.

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More Definitions for thermonuclear


How to pronounce thermonuclear (audio) How to pronounce thermonuclear (audio)

English Language Learners Definition of thermonuclear

technical : of or relating to the changes in the nucleus of atoms that happen at extremely high temperatures

More from Merriam-Webster on thermonuclear

Nglish: Translation of thermonuclear for Spanish Speakers

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