First Known Use: circa 1617
Dictionary
1fission
noun fis·sion \ˈfi-shən, -zhən\
physics : a process in which the nucleus of a heavy atom is split apart
biology : a kind of reproduction in which a cell or body divides into two or more parts and each part grows into a whole new individual
Full Definition of FISSION
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
— fis·sion·al \-shə-nəl, -zhə-\ adjective
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Origin of FISSION
Latin fission-, fissio, from findere to split — more at bite
2fission
verb
Definition of FISSION
intransitive verb
: to undergo fission
transitive verb
: to cause to undergo fission
First Known Use of FISSION
1929
FISSION[1] Defined for Kids
fission
noun fis·sion \ˈfi-shən\
Definition of FISSION for Kids
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
: the process of splitting an atomic nucleus with the release of large amounts of energy
Medical Dictionary
fission
noun fis·sion \ˈfish-ən also ˈfizh-\
Medical Definition of FISSION
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 2 b : the splitting of an atomic nucleus resulting in the release of large amounts of energy—called also nuclear fission
—fis·sion verb, fis·sioned fis·sion·ing \ˈfish-(ə-)niŋ also ˈfizh-\
—fis·sion·al \ˈfish-ən-əl also ˈfizh-\ adjective
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