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fission, nuclear

A nuclear reaction in which a single large nucleus splits into two or more smaller nuclei. In some cases, for example with uranium, energy is released in this process.

Note

The fission of uranium 235, an isotope of uranium, supplies energy for nuclear reactors and atomic bombs (see also atomic bomb).
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.