phototropism

noun pho·tot·ro·pism \fō-ˈtä-trə-ˌpi-zəm\

Definition of PHOTOTROPISM

: a tropism in which light is the orienting stimulus

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International Scientific Vocabulary

First Known Use: 1899

Medical Dictionary

noun pho·tot·ro·pism \fō-ˈtä-trə-ˌpiz-əm, ˌfōt-ō-ˈtrō-ˌpiz-əm\

: a tropism in which light is the orienting stimulus—see heliotropism

: the reversible change in color of a substance produced by the formation of an isomeric modification when exposed to radiant energy (as light)

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