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reactant

[ree-ak-tuh nt]
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SEE MORE SYNONYMS FOR reactant ON THESAURUS.COM

noun

a person or thing that reacts.
Also called interactant. Chemistry. any substance that undergoes a chemical change in a given reaction.

Origin of reactant

First recorded in 1925–30; react + -ant
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for reactant

impetus, motivation, incentive, stimulant, incitement, reactionary, spur, goad, incendiary, agitator, impulse, incitation, synergist, adjuvant, enzyme, yeast, leaven, ferment

Examples from the Web for reactant

Historical Examples of reactant

  • No matter what distance or reactant I assume, nothing we know will fit.

    Masters of Space

    Edward Elmer Smith

  • "She's been stripped of her reactant pile, Major," said Strong.

    The Revolt on Venus

    Carey Rockwell

  • What kind of reactant is Quent Miles using in that ship of yours?

    Treachery in Outer Space

    Carey Rockwell and Louis Glanzman

  • "Reactant feeding at D-9 rate," said Barret after a split-second pause.

    Sabotage in Space

    Carey Rockwell

  • I don't know who's going to be first, but I can't even strip my ship by tomorrow morning, let alone soup up the reactant.

    Treachery in Outer Space

    Carey Rockwell and Louis Glanzman

British Dictionary definitions for reactant

reactant

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
Word Origin and History for reactant

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

Online Etymology Dictionary, © 2010 Douglas Harper
reactant in Medicine

reactant

[rē-ăk′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.
reactant in Science

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.