fission

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fission
fission of a uranium nucleus

fis·sion

 (fĭsh′ən, fĭzh′-)
n.
1. The act or process of splitting into parts.
2. A nuclear reaction in which an atomic nucleus, especially a heavy nucleus, such as an isotope of uranium, splits into fragments, usually two fragments of comparable but unequal mass, and releases a few neutrons and about 100 million electron volts of energy. Nuclear fission may occur spontaneously or may be induced by the absorption of a neutron, which can initiate a nuclear chain reaction.
3. Biology An asexual reproductive process in which a unicellular organism divides into two or more independently maturing daughter cells.
v. fis·sioned, fis·sion·ing, fis·sions
v.tr.
To cause (an atom) to undergo fission.
v.intr.
To undergo fission.

[Latin fissiō, fissiōn-, a cleaving, from fissus, split; see fissi-.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

fission

(ˈfɪʃən)
n
1. the act or process of splitting or breaking into parts
2. (Biology) biology a form of asexual reproduction in single-celled animals and plants involving a division into two or more equal parts that develop into new cells
3. (General Physics) short for nuclear fission
[C19: from Latin fissiō a cleaving]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

fis•sion

(ˈfɪʃ ən)

n.
1. the act of cleaving or splitting into parts.
2. the splitting of the nucleus of an atom into nuclei of lighter atoms, accompanied by the release of energy.
3. the division of a biological organism into new organisms as a process of reproduction.
v.t.
4. to cause (an atom) to undergo fission.
Compare fusion (def. 4).
[1835–45; < Latin fissiō splitting, cleaving]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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fis·sion

(fĭsh′ən)
1. The splitting of the nucleus of an atom into two or more nuclei. The splitting occurs either spontaneously, because the nucleus has many neutrons and is unstable, or because the nucleus has collided with a free-moving neutron. The splitting of a nucleus releases one or more neutrons and energy in the form of radiation. See Note at fusion.
2. A reproductive process in which a single cell splits to form two independent cells that later grow to full size. Bacteria and other single-celled organisms usually reproduce by means of fission. Also called binary fission.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

fission

The process whereby the nucleus of a heavy element splits into (generally) two nuclei of lighter elements, with the release of substantial amounts of energy.
Dictionary of Military and Associated Terms. US Department of Defense 2005.

fission

1. A process (spontaneous or induced) during which a heavy atomic nucleus disintegrates into two lighter atoms which together have less mass than the total initial material. This lost mass is converted to energy, the amount is given by Einstein’s equation E=mc2.
2. The splitting of an atom’s nucleus to release subatomic particles and energy.
Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.fission - reproduction of some unicellular organisms by division of the cell into two more or less equal parts
agamogenesis, asexual reproduction - reproduction without the fusion of gametes
schizogony - asexual reproduction by multiple fission; characteristic of many sporozoan protozoans
2.fission - a nuclear reaction in which a massive nucleus splits into smaller nuclei with the simultaneous release of energyfission - a nuclear reaction in which a massive nucleus splits into smaller nuclei with the simultaneous release of energy
nuclear reaction - (physics) a process that alters the energy or structure or composition of atomic nuclei
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.

fission

noun splitting, parting, breaking, division, rending, rupture, cleavage, schism, scission a fission in the earth's crust
Collins Thesaurus of the English Language – Complete and Unabridged 2nd Edition. 2002 © HarperCollins Publishers 1995, 2002
Translations
إنْشِطار
štěpení
fissionspaltning
fissio
kjarnaklofningur
skilimas
atomkodola šķelšanās
nükleer bölünme

fission

[ˈfɪʃən] N (Phys) → fisión f (Bio) → escisión f
atomic/nuclear fissionfisión f atómica/nuclear
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005

fission

[ˈfɪʃən] nfission f
atomic fission, nuclear fission → fission nucléaire
Collins English/French Electronic Resource. © HarperCollins Publishers 2005

fission

n (Phys) → Spaltung f; (Biol) → (Zell)teilung f
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007

fission

[ˈfɪʃn] nfissione f
atomic/nuclear fission → fissione atomica/nucleare
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995

fission

noun : nuclear fission (ˈfiʃən)
the splitting of the nuclei of atoms.
Kernerman English Multilingual Dictionary © 2006-2013 K Dictionaries Ltd.

fis·sion

n. fisión.
1. división en partes;
2. división de un átomo para ser descompuesto y desplazar energía y neutrones.
English-Spanish Medical Dictionary © Farlex 2012
References in periodicals archive ?
of mercury (180Hg), which subsequently fissions, it said.
These errors range from minor (the control rods in Fermi's CP-1 reactor were made of cadmium, which absorbs neutrons, not of graphite, which slows them down) to fundamental conceptual errors (U-235 does not decay during a chain reaction, it fissions).
Neutrons emitted from splitting atomic nuclei are usually too fast to trigger subsequent fissions, but water has a knack for slowing down neutrons.
Nuclear power is derived from the energy produced when the nuclei of large atoms are bombarded with neutrons and split apart--a process known as nuclear fission. When each fission produces neutrons that in turn cause additional fissions, a self-sustaining "chain reaction" is set up.
1992c), the F5 and FM2 cytotypes differ by centric fissions at chromosomes 1, 3, and 6 ([ILLUSTRATION FOR FIGURE 2 OMITTED] in Sites et al.
Two basic outcomes are possible: Either the two nuclei fuse into a lasting larger one, or the emerging heavy nucleus quickly splits, or fissions, into two pieces.
Eventually, if rotated fast enough, the nucleus will deform so much it fissions, or breaks in two.
Havens of Columbia University in New York City suggest instead that a graphite fire may have been ignited during the attempted removal of "Wigner energy'--a phenomenon that occurs when neutrons, set free by nuclear fissions in the uranium oxide fuel, bounce off carbon atoms in the graphite.
Its properties with respect to capture and fission by thermal neutrons are similar to the properties of uranium-235.
The transuranics are all inherently unstable, subject to spontaneous fission or radioactive decay -- as is uranium, atomic number 92, the heaviest element known to exist in detectable amounts on earth.