nuclear

adjective
nu·​cle·​ar | \ ˈnü-klē-ər How to pronounce nuclear (audio) , ˈnyü- How to pronounce nuclear (audio) , nonstandard -kyə-lər\

Definition of nuclear

1 : of, relating to, or constituting a nucleus annexation of the suburban fringe by the nuclear metropolis— W. H. Wickwar
2a : of or relating to the atomic nucleus nuclear reaction nuclear physics
b : used in or produced by a nuclear reaction (such as fission) nuclear fuel nuclear waste nuclear energy
c(1) : being a weapon whose destructive power derives from an uncontrolled nuclear reaction
(2) : of, produced by, or involving nuclear weapons the nuclear age nuclear war
(3) : armed with nuclear weapons nuclear powers
d : of, relating to, or powered by nuclear energy a nuclear submarine the nuclear debate a nuclear plant
go nuclear
informal
: to become wildly excited or upset : to go berserk To say the crowd went wild is an understatement. The crowd went nuclear. Outside the stadium, cars were overturned and fires were set. We sportswriters huddled inside, fearing for our lives.— Tony Kornheiser

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How do you pronounce nuclear?: Usage Guide

Though disapproved of by many, pronunciations ending in \-kyə-lər\ have been found in widespread use among educated speakers including scientists, lawyers, professors, congressmen, U.S. cabinet members, and at least two U.S. presidents and one vice president. While most common in the U.S., these pronunciations have also been heard from British and Canadian speakers.

Examples of nuclear in a Sentence

Recent Examples on the Web

Germany and France, who have voiced criticism of Trump’s withdrawal from the joint nuclear deal with Iran, had openly rebuffed that plan. Washington Post, "Defense Secretary Mark Esper wants to be the leader who finally delivers on the Pentagon’s goal of outpacing China. Can he do it?," 7 Aug. 2019 Iran appeared to link the British seizure of its tanker and the ailing nuclear deal. New York Times, "Iran Says It Has Seized Another Oil Tanker in Persian Gulf," 4 Aug. 2019 Britain, France, and Germany have repeatedly recommitted to the original nuclear deal. Robin Wright, The New Yorker, "Iran’s Foreign Minister Invited to Meet Trump in the Oval Office," 2 Aug. 2019 Iran's aggressive posture follows President Trump's 2018 decision to withdraw the U.S. from the 2015 nuclear deal between Iran, the United States and other world powers. Brian Pascus, CBS News, "U.S. slaps sanctions on Iranian Foreign Minister Mohammad Javad Zarif as tensions rise," 1 Aug. 2019 The State and Treasury teams rejected those options because their actual goal is to save the nuclear deal. NBC News, "Trump to hold off on tightening limits on Iran's nuclear work," 31 July 2019 The nuclear deal had raised expectations of a better life for many Iranians, free of the chokehold of international sanctions. Mohammad Nasiri, chicagotribune.com, "Iran says say ramped-up American sanctions are blocking access to badly needed medicine," 30 July 2019 Skeptics doubted that the administration’s unilateral sanctions could truly bite after the nuclear deal opened Iran for business with Europe. Nr Editors, National Review, "The Week," 25 July 2019 Johnson has also been a supporter of the nuclear deal reached by Iran, the U.K., the U.S. and other world powers (the United States has since withdrawn from the agreement). Cnaan Liphshiz, sun-sentinel.com, "Five Jewish things to know about Boris Johnson," 24 July 2019

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

1822, in the meaning defined at sense 1

History and Etymology for nuclear

nucle(us) + -ar

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Statistics for nuclear

Last Updated

10 Aug 2019

Look-up Popularity

Time Traveler for nuclear

The first known use of nuclear was in 1822

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More Definitions for nuclear

nuclear

adjective

English Language Learners Definition of nuclear

: of, relating to, producing, or using energy that is created when the nuclei of atoms are split apart or joined together
: having or involving nuclear weapons
: of or relating to the nucleus of an atom

nuclear

adjective
nu·​cle·​ar | \ ˈnü-klē-ər How to pronounce nuclear (audio) , ˈnyü-\

Kids Definition of nuclear

1 : of, relating to, or being a nucleus (as of a cell)
2 : of or relating to the nucleus of the atom Fission is a nuclear reaction.
3 : produced by a nuclear reaction nuclear energy
4 : of, relating to, or being a weapon whose destructive power comes from an uncontrolled nuclear reaction
5 : relating to or powered by nuclear energy a nuclear submarine

nuclear

adjective
nu·​cle·​ar | \ ˈn(y)ü-klē-ər How to pronounce nuclear (audio) \

Medical Definition of nuclear

1 : of, relating to, or constituting a nucleus
2 : of, relating to, or utilizing the atomic nucleus, atomic energy, the atomic bomb, or atomic power

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More from Merriam-Webster on nuclear

Spanish Central: Translation of nuclear

Nglish: Translation of nuclear for Spanish Speakers

Britannica English: Translation of nuclear for Arabic Speakers

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