The growth of a living organism in response to gravity, as the downward growth of plant roots.(noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "geotropism" in a sentence
"Once plant life invaded the land it was subject to the action of gravity, and geotropism ( "earth-turning" G), involving an automatic and adaptive response to gravity, was developed."
"But atavistic, or vestigial, geotropism in Genesistrine -- or a million larvae start crawling, and a million little frogs start hopping -- knowing no more what it's all about than we do when we crawl to work in the morning and hop away at night."
"They give the quintessence of laboratory experiments as to what are the effects of different energies such as light (heliotropism), electricity (galvanotropism), gravity (geotropism), etc., in their reaction and influence upon the movements and actions of living organisms."