phototaxis

or pho·to·tax·y

[ foh-tuh-tak-sis ]

/ ˌfoʊ təˈtæk sɪs /

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noun Biology.

movement of an organism toward or away from a source of light.

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Origin of phototaxis

First recorded in 1900–05; photo- + -taxis

OTHER WORDS FROM phototaxis

pho·to·tac·tic

[foh-tuh-tak-tik], /ˌfoʊ təˈtæk tɪk/, adjectivepho·to·tac·ti·cal·ly, adverb

Words nearby phototaxis

photo story, photosynthate, photosynthesis, photosynthesize, photosystem, phototaxis, phototelegraphy, phototheodolite, phototherapeutics, phototherapy, photothermic

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use phototaxis in a sentence

If it acts in a one-sided way, it causes the particular form of stimulation which we call phototaxis or heliotropism.
The Wonders of Life|Ernst Haeckel

British Dictionary definitions for phototaxis

phototaxis

phototaxy

/ (ˌfəʊtəʊˈtæksɪs) /

noun

the movement of an entire organism in response to light

Derived forms of phototaxis

phototactic (ˌfəʊtəʊˈtæktɪk), 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