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verb im·pact \im-ˈpakt\

Simple Definition of impact

  • : to have a strong and often bad effect on (something or someone)

  • : to hit (something) with great force

Full Definition of impact

  1. transitive verb
  2. 1 a :  to fix firmly by or as if by packing or wedging b :  to press together

  3. 2 a :  to have a direct effect or impact on :  impinge on b :  to strike forcefully; also :  to cause to strike forcefully

  4. intransitive verb
  5. 1 :  to have an impact —often used with on

  6. 2 :  to impinge or make contact especially forcefully

im·pact·ful play \im-ˈpakt-fəl, ˈim-ˌpakt-fəl\ adjective
im·pac·tive play \im-ˈpak-tiv\ adjective
im·pac·tor also im·pact·er play \-tər\ noun

Examples of impact

  1. No one is sure how these changes will impact our relations with other countries.

  2. Both events negatively impacted her life.

  3. The tax increase will impact low-income families the most.

  4. The poor economy is impacting on small businesses.

  5. A crater was formed at the point where the meteor impacted the planet's surface.

Origin of impact

Latin impactus, past participle of impingere to push against — more at impinge

First Known Use: 1601



noun im·pact \ˈim-ˌpakt\

Simple Definition of impact

  • : the act or force of one thing hitting another

  • : a powerful or major influence or effect

Full Definition of impact

  1. 1 a :  an impinging or striking especially of one body against another b :  a forceful contact or onset; also :  the impetus communicated in or as if in such a contact

  2. 2 :  the force of impression of one thing on another :  a significant or major effect <the impact of science on our society> <an environmental impact study>

Examples of impact

  1. No one could have survived such an impact.

  2. These warnings have been heard so often that they have lost their impact.

  3. The book had a huge impact when it first came out.

  4. We need to be concerned about the environmental impacts of all this construction.

  5. She expects to make an immediate impact at work.


First Known Use of impact


Synonym Discussion of impact

impact, collision, shock, concussion mean a forceful, even violent contact between two or more things. impact may be used to imply contact between two things, at least one of which is impelled toward the other <the glass shattered on impact with the floor>. collision implies the coming together of two or more things with such force that both or all are damaged or their progress is severely impeded <the collision damaged the vehicle>. shock often denotes the effect produced by a collision and carries the suggestion of something that strikes or hits with force <the shock of falling rocks>. concussion when not in technical use, often suggests the shattering, disrupting, or weakening effects of a collision, explosion, or blow <bystanders felt the concussion of the blast>.

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February 8, 2016

to clear from accusation or blame

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