phototropism

[ foh-to-truh-piz-uhm, foh-toh-troh-piz-uhm ]

nounBotany.
  1. phototropic tendency or growth.

Origin of phototropism

1
First recorded in 1895–1900; photo- + -tropism

Words Nearby phototropism

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use phototropism in a sentence

British Dictionary definitions for phototropism

phototropism

/ (ˌfəʊtəʊˈtrəʊpɪzəm) /


noun
  1. the growth response of plant parts to the stimulus of light, producing a bending towards the light source

  2. the response of animals to light; phototaxis

Derived forms of phototropism

  • phototropic, adjective

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for phototropism

phototropism

[ fō-tŏtrə-pĭz′əm ]


  1. The growth or movement of a fixed organism toward or away from light. In plants, phototropism is a response to blue wavelengths of light and is caused by a redistribution of auxin from the illuminated side to the darker side of the shoot, resulting in quicker growth on the darker side and bending of the shoot toward the source of light. Certain sessile invertebrates also exhibit phototropism.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.