Tropism
/ˈtroʊpɪzəm/noun
A directional response of an organism or cell to an external stimulus.
Did you know?The root behind tropism is the same ancient turning-word that gave us “trope,” because a trope is literally a “turn” in meaning.
Etymological Timeline
Proto-Indo-European
PIE
*trep-
“to turn, rotate, or twist”
Ancient Greek
Greek
τροπή (tropḗ)
“a turn, turnabout, or change”
Ancient Greek
Greek
τροπικός (tropikós)
“of turning; turning point; later, relating to the solstices”
Late Latin
Latin
tropismus
“a turning or turning toward”
19th Century
English
tropism
“a turning response toward or away from a stimulus”
Modern English
English
tropism
“an organism's directional movement or growth in response to a stimulus”