nuclear energy
Americannoun
noun
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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.
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Also called atomic energy
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Electricity generated by a nuclear reactor.
Pronunciation
See nuclear ( def. ).
Etymology
Origin of nuclear energy
First recorded in 1925–30
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
On Wednesday, the secretary of energy signed an agreement by which the United States would supply Saudi Arabia with nuclear energy technology.
From Slate ● Jul. 23, 2026
The retired former government worker, 68, also believes the administration’s support for nuclear energy will be a boon for the nuclear-power-plant communities near where she grew up, in Michigan.
From The Wall Street Journal ● Jul. 11, 2026
Over the past six months, the Russell 2000 benefited from a boom in shares of technology stocks and, in particular, highly-speculative names tied to popular themes like quantum computing, nuclear energy, artificial intelligence and biotechnology.
From MarketWatch ● Jun. 30, 2026
In graduate school he studied with scientists who had worked on the Manhattan Project, and he worried that supporting nuclear energy could lead to the proliferation of weapons.
From Salon ● Jun. 26, 2026
Still, the idea of attempting to release nuclear energy in the middle of a city of three million made Groves very nervous.
From "Bomb" by Steve Sheinkin
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.