Longman Dictionary of Contemporary English homepage

Date: 1900-2000
Origin: catalysis, on the model of analyst

catalyst

 noun
     
Related topics: Chemistry
cat‧a‧lyst [countable]
1HC technical a substance that makes a chemical reaction happen more quickly without being changed itself
2 something or someone that causes an important change or event to happen
catalyst for
They hope his election will act as a catalyst for reform.
—catalytic adjective
Definition from the Longman Dictionary of Contemporary English
Advanced Learner's Dictionary.

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