- catalyst catalyst n.
1. (Chem.) a substance that initiates or accelerates a
chemical reaction without itself being affected; as,
thousands of enzymes serve in concert as calaysts to
produce the sequence of reactions we call ``life``; the
industrial production of cheap ammonia depended on finding
a good catalyst.
Note: A catalyst is never the main cause of an event, but may serve to hasten events for which the underlying causes are present prior to the appearance or occurrence of the catalyst. [WordNet 1.5 +PJC]
The Collaborative International Dictionary of English. 2000.