fission

1 of 2

noun

fis·​sion ˈfi-shᵊn 

-zhᵊn

1

: a splitting or breaking up into parts

2

: reproduction by spontaneous division of the body into two or more parts each of which grows into a complete organism

3

: the splitting of an atomic nucleus resulting in the release of large amounts of energy

fissional

ˈfi-shə-nəl 

-zhə-

adjective

fission

2 of 2

verb

fissioned; fissioning; fissions

intransitive verb

: to undergo fission

transitive verb

: to cause to undergo fission

Examples of fission in a Sentence

Recent Examples on the Web

Noun

Oklo, which Altman also chairs, is focused on the opposite reaction, fission, which generates energy by splitting an atom; fusion does so by merging atomic nuclei. Representatives for Altman, through his special acquisition company AltC, didn’t respond to a request for comment. —Emily Pandise, NBC News, 7 Mar. 2024

Most of the three-hour movie, about the creation of the atomic bomb, is guys in suits, talking about fission and geopolitics and other brainy matters over a pulsating score by Ludwig Goransson. —Alissa Wilkinson, New York Times, 3 Mar. 2024

Word History

Etymology

Noun

borrowed from Latin fissiōn-, fissiō, from fid-, variant stem of findere "to split, cleave" + -tiōn-, -tiō, suffix of verbal action — more at bite entry 1

Verb

derivative of fission entry 1

First Known Use

Noun

circa 1617, in the meaning defined at sense 1

Verb

1929, in the meaning defined at intransitive sense

Phrases Containing fission

• binary fission
• nuclear fission

Kids Definition

fission

1 of 2 noun

fis·​sion ˈfish-ən 

 also  ˈfizh-

1

: a splitting or breaking up into parts

2

: a method of reproduction in which a living cell or body divides into two or more parts each of which grows into a whole new individual

3

: the splitting of an atomic nucleus resulting in the release of large amounts of energy

fission

2 of 2 verb

fissioned; fissioning

ˈfish-(ə-)niŋ,

ˈfizh-

: to go through or cause to go through fission

Medical Definition

fission

noun

fis·​sion ˈfish-ən also ˈfizh- 

1

: a method of reproduction in which a living cell or body divides into two or more parts each of which grows into a whole new individual

2

a

: cleavage sense 2

b

: the splitting of an atomic nucleus resulting in the release of large amounts of energy

called also nuclear fission

fission verb

fissioned; fissioning ˈfish-(ə-)niŋ also ˈfizh- 

fissional

ˈfish-ən-ᵊl also ˈfizh- 

adjective