heliotropism

American  

[hee-lee-o-truh-piz-uhm, hee-lee-uh-troh-piz-uhm] / ˌhi liˈɒ trəˌpɪz əm, ˌhi li əˈtroʊ pɪz əm /

noun

1. heliotropic tendency or growth.

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heliotropism British  

/ ˌhiːlɪəʊˈtrɒpɪk, ˌhiːlɪˈɒtrəˌpɪzəm /

noun

1. the growth of plants or plant parts (esp flowers) in response to the stimulus of sunlight, so that they turn to face the sun

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heliotropism Scientific  

/ hē′lē-ŏt′rə-pĭz′əm /

1. The growth or movement of a fixed organism, especially a plant, toward or away from sunlight. Heliotropism can be easily seen in sunflowers, which slowly turn their large flowers so that they continually face the sun.

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Other Word Forms

• heliotropic adjective
• heliotropically adverb

Etymology

Origin of heliotropism

First recorded in 1850–55; helio- + -tropism

Example Sentences

The researchers have not yet identified the genes involved in heliotropism.

From Science Daily • Oct. 31, 2023

Blocking blue, ultraviolet, red or far-red light with shade boxes had no effect on the heliotropism response.

From Science Daily • Oct. 31, 2023

I tiptoed religiously by it, went on up to the big house where the three women slept, as if drawn to their abode by a sort of heliotropism.

From Tramping on Life An Autobiographical Narrative by Kemp, Harry

We notice also the reverse phenomenon, namely, that chemical changes produced in the animal destroy its heliotropism.

From Darwin and Modern Science by Seward, A. C. (Albert Charles)

Drosera rotundifolia is one of the few plants the leaves of which exhibit no trace of heliotropism.

From The Power of Movement in Plants by Darwin, Charles