heliotropism

[ hee-lee-o-truh-piz-uhm, hee-lee-uh-troh-piz-uhm ]

noun

1. heliotropic tendency or growth.

heliotropism

/ 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

heliotropism

/ 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.

Derived Forms

• ˌhelioˈtropically, adverb
• heliotropic, adjective

Word History and Origins

Origin of heliotropism¹

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

Example Sentences

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

From Science Daily

It’s heliotropism, and sunflowers are not the only plants that track the sun.

From New York Times

But light sensitivity—or heliotropism—plays a role too.

From Time

He defines "List" as "an attitude resulting from the rotation of the insect about its longitudinal axis, as heliotropism results from a rotation about an imaginary vertical axis at right angles to this."

From Project Gutenberg

Since plants possess no nerves, this identity of animal with plant heliotropism can offer but one inference—these heliotropic effects must depend upon conditions which are common to both animals and plants.

From Project Gutenberg