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nyctitropism

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

Definition of nyctitropism

plural -s
: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

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