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geotaxis

[jee-oh-tak-sis]
noun Biology.
  1. oriented movement of a motile organism toward or away from a gravitational force.

Origin of geotaxis

First recorded in 1960–65; geo- + -taxis
Related formsge·o·tac·tic [jee-oh-tak-tik] /ˌdʒi oʊˈtæk tɪk/, adjectivege·o·tac·ti·cal·ly, adverb
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for geotaxis

geotaxis

noun
  1. movement of an organism in response to the stimulus of gravity
Derived Formsgeotactic, adjectivegeotactically, adverb
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