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

But there's no such memorial for the 1980 accident in which a Titan II missile carrying a thermonuclear reactor exploded near Damascus, Arkansas. David Grossman, Popular Mechanics, "America Never Had a Chernobyl. But It Came Close.," 5 June 2019 Five billion years hence, our sun, too, will exhaust its thermonuclear fuel supply. Alan Hirshfeld, WSJ, "Book Review: Feeling Gravity’s Pull," 16 Nov. 2018 This 20-meter rocket, designed to carry thermonuclear weapons, served as a template for the original Delta rockets. Eric Berger, Ars Technica, "The Delta II rocket came, it saw, and for a time it conquered," 17 Sep. 2018 That a global audience from Washington to Pyongyang and beyond was agape at such a once inconceivable tete-a-tete in the wake of threats of thermonuclear war and scathing personal insults, is not in doubt. Washington Post, "Summit Day: What happened at historic Trump-Kim meeting?," 12 June 2018 North Korea spent decades developing nuclear weapons, culminating in the test of a thermonuclear device in 2017. Author: Steve Holland, Jack Kim, Anchorage Daily News, "Trump and North Korea’s Kim arrive in Singapore for historic summit," 10 June 2018 The North made rapid strides in its offensive capabilities last year, testing not only its first thermonuclear device but its first ballistic missiles capable of reaching the continental United States. Matt Stiles,, "Just before summit was called off, North Korea announced demolition of its nuclear test site," 24 May 2018 The same ingenuity that allowed humans to hit home runs with evolution’s curveballs has arguably created the risk of environmental destruction, resource exhaustion, anthropogenic climate change and thermonuclear war. Nathan H. Lents, WSJ, "The Botch of the Human Body," 13 Apr. 2018 Anything with a higher yield has to be either a boosted or a thermonuclear device. Andrew Karam, Popular Mechanics, "Nuclear Forensics: How Scientists Can Tell Whether North Korea Is Lying About Its Bomb Test," 7 Jan. 2016

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

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The first known use of thermonuclear was in 1938

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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

Comments on thermonuclear

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to wander slowly or to speak indistinctly

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