nuclear energy

American  

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

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

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Example Sentences

See Examples For:

nuclear energy

Amazon just made a new nuclear energy investment that could expand the capacity of America’s reactor fleet.

From Barron's ● Sep. 30, 2026

Roughly 50 companies are working on the small reactors, mostly in the U.S., said Adam Stein, director of nuclear energy and innovation at the Breakthrough Institute.

From Los Angeles Times ● Aug. 28, 2026

Published in Nature, the findings offer new insight into the structure of atomic nuclei and could have important implications for astrophysics, nuclear energy, national security, and nuclear forensics.

From Science Daily ● Aug. 21, 2026

In discussions with peers, he has likened the proposed entity to the International Atomic Energy Agency, a nongovernmental watchdog that promotes cooperation on nuclear energy.

From The Wall Street Journal ● Aug. 13, 2026

The commission’s most important bequest from the Pentagon’s nuclear energy apparatus was the Manhattan District’s network of atomic labs, which Groves had kept intact after the war.

From "Big Science" by Michael Hiltzik

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Related Words

• atomic energy
• nuclear power

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