noun nyc·ti·nas·ty

Definition of nyctinasty



  1. :  a nastic movement (as the opening and closing of some flowers) that is associated with diurnal changes of temperature or light intensity

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Origin and Etymology of nyctinasty

International Scientific Vocabulary nyct- + -nasty; probably originally formed as German nyktinastie

Seen and Heard

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to cast off or become cast off

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