noun
- heliotropic tendency or growth.
noun
- the growth of plants or plant parts (esp flowers) in response to the stimulus of sunlight, so that they turn to face the sun
1854, from heliotrope + -ism.
- 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.