Word Study
heliotropism
CIDE DICTIONARY
heliotropism, n. [Helio- + Gr. to turn.].
The phenomenon of turning toward the light, seen in many leaves and flowers. [1913 Webster]
OXFORD DICTIONARY
heliotropism, n. the directional growth of a plant in response to sunlight (cf. PHOTOTROPISM).
Derivative
heliotropic adj.
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