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[kat-l-ahyz] /ˈkæt lˌaɪz/
verb (used with object), catalyzed, catalyzing.
to act upon by catalysis.
Also, especially British, catalyse.
1885-90; cataly(sis) + (-i)ze
Related forms
catalyzer, noun Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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Examples from the web for catalyse
  • The machines they focus on are enzymes, machines which catalyse certain biochemical reactions.
  • Not to mention water, which can readily catalyse certain types of oxidation reaction.
  • It could catalyse further mergers that would bring gains of their own.
  • They rely on platinum, a metal that costs twice as much as gold, to catalyse the reaction.
  • Natural enzymes, which catalyse the reactions that make life possible, generally turn out only one enantiomer.
  • The acceptable face of government intervention now is to try to catalyse the growth of brand new industries.
  • The foundation is developing a whole series of prizes designed to catalyse clean, renewable and cost-effective energy.
  • To escape the trap they are in, they will need more than free trade to catalyse growth.
  • The social media of the day helped catalyse the reaction but eventually a new equilibrium was established.
British Dictionary definitions for catalyse


(transitive) to influence (a chemical reaction) by catalysis
Derived Forms
catalyser, (US) catalyzer, noun
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 catalyse

variant spelling of catalyze (q.v.); for spelling, see -ize. Related: Catalysed; catalysing.



1890, back-formation from catalysis on model of analyze/analysis. Related: Catalyzed; catalyzing. Probably influenced by French catalyser (1842).

Online Etymology Dictionary, © 2010 Douglas Harper
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catalyse in Medicine

catalyze cat·a·lyze (kāt'l-īz')
v. cat·a·lyzed, cat·a·lyz·ing, cat·a·lyz·es
To modify, especially to increase, the rate of a chemical reaction by catalysis.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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catalyse in Science
To modify, especially to increase, the rate of a chemical reaction through the action of a catalyst.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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