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impact

n. · v.
US //ˈɪmpækt// im·pact
  1. 1 a strong effect (n.)
    B1 Intermediate Academic

    the powerful effect that something has on a person, situation, or place.

    the significant or powerful influence or effect of an action, event, or person on another entity.

    Example

    The new recycling program had a positive impact on the local environment.

    Example

    Economists are still assessing the long-term impact of the trade agreement on small-scale manufacturing sectors across the region.

    Usage

    Often used with the preposition 'on' when functioning as a noun.

    Teacher's tip

    While common in business and academic contexts, some traditionalists prefer 'affect' or 'influence' over the verb form of 'impact'.
    Pitfall
    The new law will impact on the economy.
    The new law will impact the economy.

    When using 'impact' as a verb, do not use the preposition 'on'. Use 'on' only when 'impact' is a noun.

  2. 2 a physical collision (n.)
    B2 Upper Intermediate

    the act of one object hitting another with great force.

    the physical striking of one body against another; a high-force collision.

    Example

    The car was built to protect the passengers in the event of an impact.

    Example

    The meteor's impact created a crater several miles wide, sending debris high into the atmosphere.

    Usage

    Often used as an uncountable noun to describe the force itself.
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  1. 3 to affect something (v.)
    B2 Upper Intermediate Academic

    to have a strong effect on someone or something.

    to have a significant or strong influence or effect on a situation or person.

    Example

    The budget cuts will heavily impact the school's music program.

    Example

    The rising cost of raw materials is expected to negatively impact the company's profit margins for the third quarter.

    Usage

    Transitive verb; does not take the preposition 'on'.
  2. 4 to be stuck or wedged (v.)
    C1 Advanced Technical Medicine

    to be pushed or wedged firmly into something so it cannot move.

    to be firmly packed or wedged into a space; frequently used in medical contexts regarding teeth or blockages.

    Example

    The dentist said my wisdom tooth is impacted and needs to be removed.

    Example

    The surgeon identified an impacted gallstone that was causing significant inflammation in the surrounding tissue.

    Usage

    Often used in the passive voice or as a past participle adjective.

    Teacher's tip

    In medicine, this most commonly refers to wisdom teeth that cannot grow in properly.

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