fission

(redirected from fissions)
Also found in: Dictionary, Thesaurus, Encyclopedia.
Related to fissions: induced fission

fission

 [fish´un]
1. the act of splitting.
2. asexual reproduction in which the cell divides into two (binary fission) or more (multiple fission) daughter parts, each of which becomes an individual organism.
3. nuclear fission; the splitting of the atomic nucleus, with release of energy.
binary fission the halving of the nucleus and then of the cytoplasm of the cell, as occurs in protozoa.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

fis·sion

(fish'ŭn),
1. The act of splitting, for example, amitotic division of a cell or its nucleus.
2. Splitting of the nucleus of an atom.
[L. fissio, a cleaving, fr. findo, pp. fissus, to cleave]
Farlex Partner Medical Dictionary © Farlex 2012

fission

(fĭsh′ən, fĭzh′-)
n.
1. The act or process of splitting into parts.
2. Biology An asexual reproductive process in which a unicellular organism divides into two or more independently maturing daughter cells.
v. fis·sioned, fis·sioning, fis·sions
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

fis·sion

(fish'ŭn)
1. The act of splitting, e.g., amitotic division of a cell or its nucleus.
2. Splitting of the nucleus of an atom.
[L. fissio, a cleaving, fr. findo, pp. fissus, to cleave]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

fission

Splitting into parts.
1. The asexual reproductive process by which a single-celled organism or a single cell in a multicellular organism splits into two daughter cells.
2. An atomic event in which the nucleus of an atom splits into fragments, with the loss of a small quantity of matter and the evolution of radiational energy of at least 100 million electron volts (mV).
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

fission

see BINARY FISSION.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005

fis·sion

(fish'ŭn)
1. The act of splitting, e.g., a mitotic division of a cell or its nucleus.
2. Splitting of the nucleus of an atom.
[L. fissio, a cleaving, fr. findo, pp. fissus, to cleave]
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
of new theoretical approaches to the fission process.
dynamics of the fission processes, at least for nuclei located in the region
Xenon isotopes also result when fission creates isotopes of other elements, such as tin, antimony, or iodine, that undergo a further series of radioactive decays.
Yet many other atomic nuclei, not just ones that undergo fission, absorb neutrons of certain energies set by the value of alpha.
Eighteen individuals collected from throughout the hybrid zone and heterozygous for up to three fission rearrangements (table 1), were chosen for meiotic analyses.
In individuals heterozygous for single fission rearrangements, the frequency of telomeric associations involving the elements of the trivalents (30.3%) was comparable to that observed in chromosome-4 heterozygotes from a nonhybrid FM2 population (31.6%; Reed et al.
In the heterozygous condition, the proximal telomeres (i.e., those closest to the centromere) of the acrocentric fission products lack homologous telomeres with which to associate.
Another possibility is to look for evidence of spontaneous fission activity in meteoric material and also in hot brines taken from abyssal fractures of the earth's crust.
Meanwhile, meteorite samples and hot brines have yielded some tantalizing evidence of spontaneous fission. "There is a great temptation to admit that the observation of these events is indicative of the existence of a spontaneously fissioning superheavy element in nature," Flerov writes.