Word Study
nyctitropic
CIDE DICTIONARY
nyctitropic, a. [From Gr. ny`x, nykto`s, night + turning.].
Turning or bending at night into special positions. [1913 Webster]
" Nyctitropic movements of plants usually consist in a folding or drooping of the leaves, the advantage being in lessening the radiation of heat." [1913 Webster]
OXFORD DICTIONARY
nyctitropic, adj. Bot. (of plant movements) occurring at night and caused by changes in light and temperature.
Etymology
Gk nukti- comb. form of nux nuktos night + tropos turn
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