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[an-hahy-druh s] /ænˈhaɪ drəs/
adjective, Chemistry
with all water removed, especially water of crystallization.
Origin of anhydrous
1810-20; < Greek ánȳdros waterless (with etymological h restored). See an-1, hydro-1, -ous Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for anhydrous
  • Indeed, the next category on the beauty horizon is anhydrous products, which do not require water to use them.
  • anhydrous hydrogen chloride is hydrogen chloride that is free from water.
  • Records note workers' exposure to anhydrous chlorine and boron trichloride vapors.
  • anhydrous ammonia is a major source of nitrogen as a fertilizer for corn and other crops.
  • anhydrous bromine is less reactive toward many metals than hydrated bromine, however.
British Dictionary definitions for anhydrous


containing no water, esp no water of crystallization
Word Origin
C19: from Greek anudros; see an-, hydro-
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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Word Origin and History for anhydrous

"containing no water," 1819, a modern coinage from Greek an-, privative prefix (see an- (1)), + hydor "water" (see water (n.1)). Greek did have anhydros "waterless," used of arid lands or corpses that had not been given proper funeral rites.

Online Etymology Dictionary, © 2010 Douglas Harper
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anhydrous in Medicine

anhydrous an·hy·drous (ān-hī'drəs)
Without water, especially water of crystallization.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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anhydrous in Science
Not containing water, especially water of crystallization.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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