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reactant

[ree-ak-tuh nt] /riˈæk tənt/
noun
1.
a person or thing that reacts.
2.
Also called interactant. Chemistry. any substance that undergoes a chemical change in a given reaction.
Origin
1925-1930
1925-30; react + -ant
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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Examples from the web for reactant
  • After the reactant gases react and deposit on the substrate, the exhaust gases flow toward and out the molybdenum exhaust ring.
British Dictionary definitions for reactant

reactant

/rɪˈæktənt/
noun
1.
a substance that participates in a chemical reaction, esp a substance that is present at the start of the reaction Compare product (sense 4)
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 reactant

1901 (n.), 1911 (adj.), from react + -ant.

Online Etymology Dictionary, © 2010 Douglas Harper
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reactant in Medicine

reactant re·ac·tant (rē-āk'tənt)
n.
A substance participating in a chemical reaction, especially a directly reacting substance present at the start of the reaction.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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reactant in Science
reactant
  (rē-āk'tənt)   
A substance participating in a chemical reaction, especially one present at the start of the reaction.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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10
12
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