noun nyc·tit·ro·pism \nikˈti‧trəˌpizəm\

Definition of nyctitropism



  1. :  a sleep movement in plants characterized by response to a stimulus that is greatest or exclusively from one direction — compare nyctinasty

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Origin and Etymology of nyctitropism

International Scientific Vocabulary nyct- + -tropism

Seen and Heard

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a rounded knoll or a ridge of ice

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