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catalyst

n.
US //ˈkætəɫəst// UK //kˈætɐlˌɪst// cat·a·lyst
  1. 1 chemistry (n.)
    C1 Advanced Technical Science

    a substance that makes a chemical reaction happen faster without being used up itself.

    a substance that increases the rate of a chemical reaction by lowering the activation energy without undergoing any permanent chemical change.

    Example

    The scientist added a metal catalyst to the mixture to speed up the experiment.

    Example

    In industrial chemistry, platinum often serves as a catalyst to facilitate the production of nitric acid from ammonia.

    Usage

    Usually functions as a countable noun in scientific reports.

  2. 2 a person or event that causes change (n.)
    C1 Advanced Academic

    a person or event that causes a major change or action to start.

    an agent, person, or event that precipitates a process or significant change.

    Example

    The new law was the catalyst for a huge protest in the city centre.

    Example

    The sudden resignation of the CEO acted as a catalyst for the long-overdue restructuring of the entire department.

    Usage

    Often used with the preposition 'for'.

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  1. 3 literature (n.)
    C2 Proficiency Academic Technical Theatre

    an event at the start of a story that gets the main action moving.

    an inciting incident within a narrative structure that initiates the primary conflict or plot progression.

    Example

    The discovery of the secret letter is the catalyst for all the drama in the play.

    Example

    Critics argue that the protagonist's chance encounter in the first act serves as the essential catalyst for his eventual downfall.

Origin

From catalysis + -ist.

Word family

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