nuclear energy

American  

[noo-klee-er en-er-jee, nyoo-] / ˈnu kli ər ˈɛn ər dʒi, ˈnyu- /

noun

1. energy released by reactions within atomic nuclei, as in nuclear fission or fusion.

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nuclear energy British  

noun

1. Also called: atomic energy.  energy released during a nuclear reaction as a result of fission or fusion

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nuclear energy Scientific  

1. The energy released by the nucleus of an atom as the result of nuclear fission, nuclear fusion, or radioactive decay. The amount of energy released by the nuclear fission of a given mass of uranium is about 2,500,000 times greater than that released by the combustion of an equal mass of carbon. And the amount of energy released by the nuclear fusion of a given mass of deuterium is about 400 times greater that that released by the nuclear fission of an equal mass of uranium.

2. Also called atomic energy

3. Electricity generated by a nuclear reactor.

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nuclear energy Cultural  

1. Energy obtained from nuclear reactions.

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Pronunciation

See nuclear ( def. ).

Etymology

Origin of nuclear energy

First recorded in 1925–30

Example Sentences

There are also early conversations around nuclear energy co-operation as Kenya looks to diversify its long-term energy strategy.

From BBC • May 12, 2026

However, Wang added, “China supports Iran’s efforts to safeguard its national sovereignty and security,” including its right to develop nuclear energy for peaceful purposes.

From Slate • May 7, 2026

SpaceX alumni have gone on to found companies focused on AI and robotics, nuclear energy and manufacturing.

From MarketWatch • May 7, 2026

Simultaneously, it invested heavily in renewable and nuclear energy.

From Barron's • May 4, 2026

“It may be that the day of useful nuclear energy is not so far distant after all,” he wrote to his fellow cyclotron builder Alexander Allen.

From "Big Science" by Michael Hiltzik

Related Words

• atomic energy
• nuclear power