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The movement of an organism in response to the light of the sun.
he′li·o·tac′tic (-tăk′tĭk) adj.
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.
(Physiology) movement of an entire organism in response to the stimulus of sunlight
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
he•li•o•tax•is(ˌhi li oʊˈtæk sɪs)
movement of an organism toward or away from sunlight.
he`li•o•tac′tic (-tɪk) adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
a tendency of certain plants to move in response to sunlight.See also: Plants
-Ologies & -Isms. Copyright 2008 The Gale Group, Inc. All rights reserved.