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.

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

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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