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[hahy-druh-thur-muh l] /ˌhaɪ drəˈθɜr məl/
adjective, Geology
noting or pertaining to the action of hot, aqueous solutions or gases within or on the surface of the earth.
Origin of hydrothermal
1840-50; hydro-1 + thermal
Related forms
hydrothermally, adverb Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for hydrothermal
  • Other scientists still think that first step happened at the mouths of so-called hydrothermal vents, at the bottom of the sea.
  • hydrothermal vents are geysers located on the ocean floor in the deep sea.
  • The hydrothermal model, on the other hand, says the hot spring fluids deposited the gold inside the rocks.
  • They've adapted to thrive at the edge of hydrothermal vents, which spew superheated water saturated with toxic chemicals.
  • hydrothermal vents on the planet's seafloor may infuse the alien ocean with chemical energy sources.
  • Swarms of yeti crabs and a ghostly octopus are among the new species spotted near hydrothermal vents, a new study says.
  • Some signs suggest that whale-fall ecosystems have exchanges with other deep-seafloor communities, such as hydrothermal vents.
British Dictionary definitions for hydrothermal


of or relating to the action of water under conditions of high temperature, esp in forming rocks and minerals
Derived Forms
hydrothermally, 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
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Word Origin and History for hydrothermal

1852, from hydro- + thermal (adj.); 1855 in geology.

Online Etymology Dictionary, © 2010 Douglas Harper
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hydrothermal in Science
Relating to or produced by hot water, especially water heated underground by the Earth's internal heat. ◇ Hydrothermal energy is power that is generated using the Earth's hot water.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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