formation

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formation

 [for-ma´shun]
1. the process of giving shape or form; the creation of an entity, or of a structure of definite shape.
2. a structure of definite shape.
chiasma formation the process by which a chiasma is formed; it is the cytologic basis of genetic recombination, or crossing over.
compromise formation in psychoanalysis a substituted idea or act representing and permitting partial expression of a repressed conflict.
concept formation the ability to organize a variety of information to form thoughts and ideas, a cognitive performance component in occupational therapy.
reaction formation a defense mechanism in which a person adopts conscious attitudes, interests, or feelings that are the opposites of unconscious feelings, impulses, or wishes. For example, a person may use revulsion or repugnance to defend against an unconscious desire or attraction.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

for·ma·tion

(fōr-mā'shŭn), [TA]
1. A formation; a structure of definite shape or cellular arrangement.
2. That which is formed.
3. The act of giving form and shape.
Synonym(s): formatio (1) [TA]
Farlex Partner Medical Dictionary © Farlex 2012

for·ma·tion

(fōr-mā'shŭn)
1. Shape, configuration, arrangement; the way in which anything is formed.
2. That which is so formed.
3. The act of giving form and shape.
Synonym(s): formatio (1) [TA] .
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

formation

any of the main natural vegetation types extending over a large area that is created by the nature of the climate. Examples include tundra, steppe, rainforest and coniferous forest.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005

for·ma·tion

(fōr-mā'shŭn)
1. A structure of definite shape or cellular arrangement.
2. That which is formed.
3. The act of giving form and shape.
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
The effect of chromosome 5B on synapsis and chiasma formation in wheat, Triticum aestivum cv.
Detection of homoeologous chiasma formation in Triticum durum x Thinopyrum bessarabicum hybrids using genomic in situ hybridization.
Effects of supernumerary heterochromatin on chiasma formation and chromosome segregation in Dociostaturus genei (Orthoptera).
In this male, complete synapsis occurred between YR and [X.sub.2] wth interstitial chiasma formation. YL is heterochromatic (as in the XY individuals) and only a distal association occurs between it and [X.sub.1]R.