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reactant

[ ree-ak-tuhnt ]
/ riˈæk tənt /
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noun
a person or thing that reacts.
Also called interactant. Chemistry. any substance that undergoes a chemical change in a given reaction.
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Origin of reactant

First recorded in 1925–30; react + -ant
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use reactant in a sentence

British Dictionary definitions for reactant

reactant
/ (rɪˈæktənt) /

noun
a substance that participates in a chemical reaction, esp a substance that is present at the start of the reactionCompare product (def. 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

Scientific definitions for reactant

reactant
[ rē-ăk′tənt ]

A substance participating in a chemical reaction, especially one present at the start of the reaction.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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