nuclear

adjective

nu·​cle·​ar ˈnü-klē-ər How to pronounce nuclear (audio) ˈnyü- How to pronounce nuclear (audio)
 nonstandard  -kyə-lər
1
: of, relating to, or constituting a nucleus
annexation of the suburban fringe by the nuclear metropolisW. H. Wickwar
2
a
: 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
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.

Phrases
go nuclear
informal
: to become wildly excited or upset : 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

Examples of nuclear in a Sentence

Recent Examples on the Web Having said that, the Iran nuclear target is a difficult target. CBS News, 6 Oct. 2024 These experimental craft included the longest vehicle ever, an overland train created to restock nuclear silos and this, the LCC-1 Sno-Train. Owen Bellwood / Jalopnik, Quartz, 5 Oct. 2024 Israel has an obligation to its people to destroy Iran’s nuclear facilities. Letters To The Editor, The Mercury News, 4 Oct. 2024 The strategy became clear early on, when Walz blamed Trump for enabling Tehran’s march toward a nuclear weapon by withdrawing from the Iran nuclear deal; the Iranian regime’s breakout time to develop weapons-grade uranium for a bomb is now only a matter of weeks. Eric Cortellessa, TIME, 2 Oct. 2024 See all Example Sentences for nuclear 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'nuclear.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

nucle(us) + -ar

First Known Use

1822, in the meaning defined at sense 1

Time Traveler
The first known use of nuclear was in 1822

Dictionary Entries Near nuclear

Cite this Entry

“Nuclear.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/nuclear. Accessed 15 Oct. 2024.

Kids Definition

nuclear

adjective
nu·​cle·​ar ˈn(y)ü-klē-ər How to pronounce nuclear (audio)
1
: of, relating to, or being a nucleus (as of a cell)
2
: of, relating to, or using the atomic nucleus
nuclear reactions
3
: being or relating to energy or a weapon that involves a nuclear reaction
nuclear energy
a nuclear war
nuclear power plants

Medical Definition

nuclear

adjective
nu·​cle·​ar ˈn(y)ü-klē-ər How to pronounce nuclear (audio)
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
Last Updated: - Updated example sentences
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