nuclear

play
adjective nu·cle·ar \ ˈnü-klē-ər , ˈnyü- , nonstandard -kyə-lər \
Updated on: 11 Sep 2017

Definition of nuclear

1 :of, relating to, or constituting a nucleus
  • annexation of the suburban fringe by the nuclear metropolis
  • —W. H. Wickwar
2 a :of or relating to the atomic nucleus
  • nuclear reaction
  • nuclear physics
b :used in or produced by a nuclear (see nuclear 2) 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?

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.


Recent Examples of nuclear from the Web

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

Other Cell Biology Terms



NUCLEAR Defined for English Language Learners

nuclear

play
adjective

Definition of nuclear for English Language Learners

  • : 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 Defined for Kids

nuclear

play
adjective nu·cle·ar \ ˈnü-klē-ər , ˈnyü- \

Definition of nuclear for Students

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

Medical Dictionary

nuclear

play
adjective nu·cle·ar \ ˈn(y)ü-klē-ər \

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

Learn More about nuclear


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