nuclear

[ noo-klee-er, nyoo-or, by metathesis, -kyuh-ler ]

adjective

1. pertaining to or involving atomic weapons:

   nuclear war.

2. operated or powered by atomic energy:

   a nuclear submarine.

3. (of a nation or group of nations) having atomic weapons.
4. of, relating to, or forming a nucleus.
5. of, relating to, or like the nuclear family:

   nuclear bonds.

noun

, Informal.

1. nuclear energy:

   switching to nuclear as a power source.

nuclear

/ ˈnjuːklɪə /

adjective

1. of, concerned with, or involving the nucleus of an atom

   nuclear fission

2. biology of, relating to, or contained within the nucleus of a cell

   a nuclear membrane

3. of, relating to, forming, or resembling any other kind of nucleus
4. of, concerned with, or operated by energy from fission or fusion of atomic nuclei

   a nuclear weapon

5. involving, concerned with, or possessing nuclear weapons

   nuclear war

   a nuclear strike

nuclear

/ no̅o̅′klē-ər /

1. Relating to or forming a cell nucleus.
2. Relating to atomic nuclei.
3. Using energy derived from the nuclei of atoms through fission or fusion reactions.

Pronunciation Note

In pronouncing nuclear, the second and third syllables are most commonly said as [-klee-er], a sequence of sounds that directly reflects the spelled sequence ‑cle·ar. In recent years, a somewhat controversial pronunciation has come to public attention, with these two final syllables said as [-ky, uh, -ler]. Since [-klee-er], the common pronunciation of ‑cle·ar, might also be represented, broadly, as [-kl, uh, -yer], the [-ky, uh, -ler] pronunciation can be seen as coming from a process of metathesis, in which the [l] and the [y] change places. The resulting pronunciation is reinforced by analogy with such words as molecular, particular, and muscular, and although it occurs with some frequency among highly educated speakers, including scientists, professors, and government officials, it is disapproved of by many.

Other Words From

• in·ter·nu·cle·ar adjective
• mul·ti·nu·cle·ar adjective
• post·nu·cle·ar adjective

Word History and Origins

Origin of nuclear¹

1840–50; nucle(us) + -ar ¹; compare French nucléaire

Example Sentences

Trump pulled out of a nuclear deal with Iran that was struck by the Obama administration in 2015.

From Salon

And some of his most destructive work, like accelerating the Iranian nuclear program by pulling out of the Joint Comprehensive Plan of Action in 2018, or imposing economic sanctions on Venezuela so severe that they catalyzed a mass migration to the United States that he was able to blame on Joe Biden and Kamala Harris, were the equivalent of planting bombs that go off long after you’ve left the room.

From Slate

This time, he’s saying with his early picks, there will be no one second guessing the leader or, in the words of his son, thinking they “know better” than a man with the nuclear codes.

From Salon

“I mean it moved from a five-alarm fire to nuclear war.”

From Salon

“We understood the Soviet Union was an existential threat, certainly with its nuclear capabilities, it was, and Russia is, but China is even more sinister. It's more insidious in what they have done under this communist regime.”

From Salon

Related Words

• basic
• essential
• fundamental
• important
• key
• paramount
• pivotal
• significant