: phototropism in which sunlight is the orienting stimulus

Word History

Etymology

borrowed from French héliotropisme, from hélio- helio- + -tropisme -tropism, after héliotrope -tropism

Note: The term was probably introduced by the Swiss naturalist Jean Senebier (1742-1809) in Physiologie végétale, tome 3 (Geneva, 1800?), p. 182.

First Known Use

circa 1854, in the meaning defined above

Time Traveler
The first known use of heliotropism was circa 1854

Browse Nearby Words

Cite this Entry

“Heliotropism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/heliotropism. Accessed 20 Mar. 2025.

Kids Definition

heliotropism

noun
: a turning or curving (as of a sunflower head) toward the sunlight

Medical Definition

heliotropism

noun
: phototropism in which sunlight is the orienting stimulus
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