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tropism

[troh-piz-uh m] /ˈtroʊ pɪz əm/
noun, Biology
1.
an orientation of an organism to an external stimulus, as light, especially by growth rather than by movement.
Origin
1895-1900
1895-1900; independent use of -tropism
Related forms
tropismatic
[troh-piz-mat-ik] /ˌtroʊ pɪzˈmæt ɪk/ (Show IPA),
adjective
tropistic
[troh-pis-tik] /troʊˈpɪs tɪk/ (Show IPA),
adjective
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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British Dictionary definitions for tropismatic

tropism

/ˈtrəʊpɪzəm/
noun
1.
the response of an organism, esp a plant, to an external stimulus by growth in a direction determined by the stimulus
Derived Forms
tropismatic, adjective
tropistic (trəʊˈpɪstɪk) adjective
Word Origin
from Greek tropos a turn
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for tropismatic
tropism
1899, "tendency of an animal or plant to turn or move in response to a stimulus," abstracted from geotropism, ult. from Gk. tropos (see trope).
Online Etymology Dictionary, © 2010 Douglas Harper
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tropismatic in Medicine

tropism tro·pism (trō'pĭz'əm)
n.
The turning or bending movement of a living organism or part toward or away from an external stimulus, such as light, heat, or gravity.


tro'pic, tro·pis'tic adj.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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tropismatic in Science
tropism
  (trō'pĭz'əm)   
The growth or movement of a living organism or anatomical structure toward or away from an external stimulus, such as light, heat, or gravity. See also geotropism, hydrotropism, phototropism.

tropistic adjective
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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Encyclopedia Article for tropismatic

tropism

response or orientation of a plant or certain lower animals to a stimulus that acts with greater intensity from one direction than another. It may be achieved by active movement or by structural alteration. Forms of tropism include phototropism (response to light), geotropism (response to gravity), chemotropism (response to particular substances), hydrotropism (response to water), thigmotropism (response to mechanical stimulation), traumatotropism (response to wound lesion), and galvanotropism, or electrotropism (response to electric current). Most tropic movements are orthotropic; i.e., they are directed toward the source of the stimulus. Plagiotropic movements are oblique to the direction of stimulus. Diatropic movements are at right angles to the direction of stimulus.

Learn more about tropism with a free trial on Britannica.com
Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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