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

The PM was asked by journalists if the UK should be preparing for nuclear war at a press conference to close the G20 summit of the world's largest economies in Brazil.

From BBC

Meanwhile, earlier on Tuesday, Putin approved changes to Russia’s nuclear doctrine, setting out new conditions under which the country would consider using its arsenal.

From BBC

Under the changes, a large attack on Russia with conventional missiles, drones or aircraft could meet the criteria for a nuclear response, as could an attack on Belarus or any critical threat to Russia's sovereignty.

From BBC

On Tuesday, the Kremlin approved its updated nuclear doctrine - which says that any aggression from a non-nuclear state, if backed by a nuclear power, will be regarded as a joint attack on Russia.

From BBC

Given it has the world’s largest army and navy, Washington is now concerned that the country is building a bigger nuclear arsenal.

From BBC

Related Words

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