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Related to nyctinastic: nyctinasty


A diurnal movement of plant parts, such as the opening during the day and closing during the night of certain flowers.

[Greek nux, nukt-, night; see nekw-t- in Indo-European roots + -nasty.]

nyc′ti·nas′tic (-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.


(Botany) botany a nastic movement, such as the closing of petals, that occurs in response to the alternation of day and night
[C20: from Greek nukt-, nux night + -nasty]
ˌnyctiˈnastic adj
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
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But there may be other nyctinastic candidates that bloom in late May in the same climate and at the same time as buttercups and wild roses, such as chickweed, which has star-shaped flowers and is actually named Stellaria media.
Protein levels may vary as a result of a light stimulus, as would be assumed in heliotropic leaf movement, or by a rhythm endogenous to the plant and at least partially independent of external stimuli, such as daily nyctinastic leaf folding of S.