nuclear

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

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

The B-21 Raider bomber will be a heavy strategic bomber capable of carrying nuclear or conventional weapons. Kyle Mizokami, Popular Mechanics, "Next Stop for the Air Force’s New Bomber: First Flight," 11 Apr. 2019 The Navy says the delay is necessary to resolve issues with the ship’s nuclear propulsion system and elevators designed to lift munitions up to the hangar. Kyle Mizokami, Popular Mechanics, "The Navy’s Newest Aircraft Carrier Is Delayed, Yet Again," 28 Mar. 2019 The return—after abruptly vacating the de facto embassy Friday—restores some trust lost as nuclear talks have faltered since last month’s no-deal summit between North Korean leader Kim Jong Un and President Trump, security analysts say. Timothy W. Martin, WSJ, "North Korea Returns to Liaison Office With South Three Days After Pulling Out," 25 Mar. 2019 Anyone who has ventured into online gaming knows text chat can approach nuclear-waste-levels of toxicity. Gordon Mah Ung, PCWorld, "Intel hopes to clean up toxic speech in game chat with AI and machine learning," 20 Mar. 2019 Donald Trump declared North Korea no longer poses a nuclear threat to the world, satellite images revealed the country has spent the past several months upgrading its ability to make solid-fuel ballistic missiles. Larry Greenemeier, Scientific American, "Satellite Images Hint North Korea Won’t Disarm Anytime Soon," 5 July 2018 Retaliatory airstrikes ended after Pakistan shot down and captured an Indian pilot, and his release this month has headed off escalation between the two nuclear powers—at least for a while. The Editorial Board, WSJ, "China Shields a Jihadist," 15 Mar. 2019 But at the same time, the legacies of liberalism and policies like social security and then grassroots movements, such as the nuclear freeze movement or the gay rights movement or feminism, are very much alive and well in the ’80s. Robert Sullivan, Vogue, "Political Division? That’s Nothing New," 7 Mar. 2019 According to the report, the nuclear effort was pushed by former National Security Adviser Michael Flynn, who was fired in early 2017. Chad Day, The Seattle Times, "Flynn pushed to share nuclear tech with Saudis, report says," 20 Feb. 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

20 Apr 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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