To counteract is to work against something in an attempt to reverse it or cancel it out. You can try to counteract the neighbors' annoyance at your loud music by bringing them some homemade brownies.

When you counteract something, you act counter — or in opposition — to it. To counteract rising global temperatures, we have to reduce the greenhouse gases flowing into the atmosphere. In order to counteract the effects of a long sleepless night, you may want to drink a cup of coffee or tea. And a good way to counteract a limited vocabulary is to learn a new word every day!

Definitions of counteract
  1. verb
    act in opposition to
    synonyms: antagonise, antagonize
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    type of:
    act, move
    perform an action, or work out or perform (an action)
  2. verb
    oppose or check by a counteraction
    synonyms: countercheck
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    type of:
    check, contain, control, curb, hold, hold in, moderate
    lessen the intensity of; temper; hold in restraint; hold or keep within limits
  3. verb
    oppose and mitigate the effects of by contrary actions
    “This will counteract the foolish actions of my colleagues”
    synonyms: counterbalance, countervail, neutralize
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    counteract the normal operation of (an automatic gear shift in a vehicle)
    type of:
    cancel, offset, set off
    make up for
  4. verb
    destroy property or hinder normal operations
    synonyms: countermine, sabotage, subvert, undermine, weaken
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    cause to run off the tracks
    type of:
    refuse to go along with; refuse to follow; be disobedient
Word Family

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