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Tropism: phototropism.

[From Greek tropē, a turning; see -tropic.]
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.




n combining form
(Biology) indicating a tendency to turn or develop in response to a certain stimulus: phototropism.
[from Greek tropos a turn]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈtroʊ pɪz əm)

the orientation of an organism toward or away from a stimulus, as light.
[1895–1900; independent use of -tropism]
tro•pis′tic (-ˈpɪs tɪk) adj.


var. of -tropy.
[see -tropy, -ism]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
Lumbar juxta-facet joint cysts in association with facet joint orientation, -tropism and -arthritis: A case-control study.