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.
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
The four companies were defense technology companies Anduril Industries and Shield AI; Uber cofounder Travis Kalanick’s new venture, Atoms; and El Segundo-based nuclear energy startup Valar Atomics.
From Los Angeles Times ● Aug. 21, 2026
Ian Chun, senior research analyst at Sands Capital with $56 billion under management, commented that industrial companies in Korea were set to benefit from the build-out of power infrastructure, grid modernization and nuclear energy.
From MarketWatch ● Aug. 13, 2026
If the second reactor is shut down Romania will, like Hungary, be temporarily without any nuclear energy production.
From BBC ● Jul. 30, 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
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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.