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catalyst

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noun [countable] catalyst pronunciation in American English /ˈkæt(ə)lɪst/ 
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singularcatalyst
pluralcatalysts
  1. 1
    someone or something that causes something to happen or change
    catalyst for:

    The new development will act as a catalyst for growth in business and tourism.

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chicken raffle

any random process, such as a competition in which a name is drawn from a hat

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