nuclear fission

[ noo-klee-er fish-uhn ]

noun

1. fission ( def 2 ).

nuclear fission

noun

1. See nuclear fusion
   the splitting of an atomic nucleus into approximately equal parts, either spontaneously or as a result of the impact of a particle usually with an associated release of energy Sometimes shortened tofission Compare nuclear fusion

fission, nuclear

1. 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.

Pronunciation Note

See nuclear ( def ).

Notes

The fission of uranium 235, an isotope of uranium, supplies energy for nuclear reactors and atomic bombs (see also atomic bomb ).

Word History and Origins

Origin of nuclear fission¹

First recorded in 1885–90

Example Sentences

When “nuclear energy” is discussed, it’s almost always in reference to nuclear fission, which generates energy by splitting atoms—and is the source of power for nuclear weapons and all of the nuclear generators in operation today.

From Time

Whereas atomic bombs are based on nuclear fission, H-bombs harness nuclear fusion, the melding of atomic nuclei, in conjunction with fission, resulting in much larger blasts.

From Science News

If enough uranium clumps together — about the mass of a grain of sand — it could initiate a chain of nuclear fission reactions, or the splitting of atomic nuclei.

From Science News

Some foreign power, concerned about this country's growing mastery of nuclear fission?

From Project Gutenberg

If it's not a new wrinkle in nuclear fission, it's a gun to shoot around corners and down winding staircases.

From Project Gutenberg