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English definition of “catalyst”


noun [C]     /ˈkæt.əl.ɪst/ US  /ˈkæt̬-/
specialized chemistry something that makes a chemical reaction happen more quickly without itself being changed Chemistry - general words an event or person that causes great change : The high suicide rate acted as a catalyst for change in the prison system .Causing things to happen
(Definition of catalyst noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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