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

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 Between 1945 and 1992, the United States conducted more than 200 above-ground nuclear weapons tests, releasing harmful radioactive material into the air and blanketing parts of the country, especially New Mexico. Ben Ray Luján, CNN, 12 May 2022 The border closures have hammered the economy, which is already struggling under international sanctions imposed in response to Pyongyang’s nuclear weapons and missile program. Dasl Yoon, WSJ, 12 May 2022 But if Washington ignores the threats, Putin may authorize a new round of nuclear weapons exercises, Haines added. Washington Post, 11 May 2022 The test represented North Korean leader Kim Jong Un’s recent vow to ramp up nuclear weapons development. Editors, USA TODAY, 11 May 2022 Sweden even had a nuclear weapons program but scrapped it in the 1960s. Karl Ritter, The Christian Science Monitor, 10 May 2022 Sweden even had a nuclear weapons program but scrapped it in the 1960s. Karl Ritter, ajc, 10 May 2022 State news features clips of the U.K. being annihilated with nuclear weapons. Tom Mctague, The Atlantic, 9 May 2022 Meanwhile, a Foreign Ministry spokesman said Friday that Russia has no intention of deploying tactical nuclear weapons in Ukraine. Democrat-gazette Staff From Wire Reports, Arkansas Online, 7 May 2022 See More

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.

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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Time Traveler for nuclear

Time Traveler

The first known use of nuclear was in 1822

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Dictionary Entries Near nuclear

nucleal reaction

nuclear

nuclear bomb

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Statistics for nuclear

Last Updated

14 May 2022

Cite this Entry

“Nuclear.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/nuclear. Accessed 19 May. 2022.

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More Definitions for nuclear

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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