Catalyst is defined as a substance that speeds up the rate of a chemical reaction.(noun)
An example of catalyst is using a catalytic converter to change carbon monoxide into carbon dioxide.
The definition of a catalyst is someone or something that speeds up or brings about an event.(noun)
An example of catalyst is how President Bush's claims that Iraq had weapons of mass destruction started the war in Iraq.
See catalyst in Webster's New World College Dictionary
See catalyst in American Heritage Dictionary 4
Origin: From catalysis.
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