heliotropism(redirected from heliotropical)
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A form of phototaxis, and perhaps of thermotaxis, in which there is a tendency to growth or movement toward (positive heliotaxis) or away from (negative heliotaxis) the sun or the sunlight.
[helio- + G. taxis, orderly arrangement]
Growth or orientation of a sessile organism, especially a plant, toward or away from the light of the sun.
he′li·o·tro′pic (-ə-trō′pĭk) adj.
heliotropism(hē″lē-ŏt′rō-pĭzm) [″ + trepein, to turn, + -ismos, condition]
The tendency of living organisms to turn or grow toward the sun.