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1. (chemistry) a substance that initiates or accelerates a chemical reaction without itself being affected
   - accelerator
    
2. Something that causes an important event to happen
   "the invasion acted as a catalyst to unite the country"

Derived forms: catalysts

See also: catalyze [N. Amer]

Type of: activator, causal agency, causal agent, cause

Antonym: anticatalyst

Encyclopedia: Catalyst