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Synonyms

counteract

American  
[kaun-ter-akt] / ˌkaʊn tərˈækt /

verb (used with object)

  • counteracts,
    present (3rd person singular)
  • counteracted,
    past participle,  past
  • counteracting
    present participle
  1. to act in opposition to; frustrate by contrary action.

    Synonyms:
    thwart, contravene, counterbalance, neutralize

counteract British  
/ ˌkaʊntərˈækt /

verb

  1. (tr) to oppose, neutralize, or mitigate the effects of by contrary action; check

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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Etymology

Origin of counteract

First recorded in 1670–80; counter- + act


Explanation

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!

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Vocabulary lists containing counteract

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

The researchers found that energy losses within the plasma can naturally counteract this effect.

From Science Daily ● Oct. 10, 2026

Idaho french-fry maker Lamb Weston Holdings said it raised prices in North America to counteract rising costs for everything but potatoes.

From The Wall Street Journal ● Aug. 1, 2026

In writing history, there must be intense rigor — evidence is important and if you have evidence that should counteract any bias or hypothesis.

From Los Angeles Times ● Jul. 21, 2026

Phone companies have also introduced features which help people track their screen time and restrict access to certain apps in an attempt to counteract the addictive loop many of us get caught in.

From BBC ● Jun. 28, 2026

In other words, just like a vast majority of the crewmen, my job is to run side to side across the deck and back again to counteract the rolling motion of the sea.

From "Challenger Deep" by Neal Shusterman

This mysterious form of energy produces an outward pressure that counteracts gravity and prevents complete collapse.

From Science Daily ● Jun. 14, 2026

Gravity makes dark matter clump together, but dark energy counteracts this effect.

From New York Times ● May 23, 2024

Now, researchers report that a once-promising new drug, an antibody that counteracts a pernicious toxin in the viper’s venom, has failed in animal trials.

From Science Magazine ● Jan. 16, 2024

"I do believe that we can win," he counteracts, "and I won't stop fighting until we do."

From BBC ● Jan. 12, 2024

He did this by adding a cosmological constant, an as yet undetected force that counteracts the force of gravity.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife

But a sharp fall in food inflation counteracted increases elsewhere.

From BBC ● Jun. 17, 2026

And one 10-second play from Friday’s Game 2 shows just how the Knicks have counteracted the player known as The Alien—by manipulating space and time.

From The Wall Street Journal ● Jun. 7, 2026

Drones can also be counteracted with “kinetic” systems, which can shoot down drones.

From Barron's ● Mar. 4, 2026

The second is when the key holds are removed and the self-reinforcing dynamics are counteracted by, for example, a new bumper harvest or the provision of scaled-up humanitarian assistance.

From Salon ● Apr. 30, 2024

I guess Joey and I counteracted the brain-loss effect caused by Chas Becker’s brilliance.

From "Winger" by Andrew Smith

“The forecast is shaped by two counteracting forces,” said Asa Johansson, director of policy studies at the OECD.

From The Wall Street Journal ● Mar. 26, 2026

The researchers also observed brain activity patterns that resembled the effects of a good night's sleep, counteracting the typical brain changes associated with sleep deprivation.

From Science Daily ● Dec. 29, 2025

It has an inclined tourbillon, a feature aimed at improving accuracy by counteracting gravity, which adds to its rarity in the watch world.

From Salon ● Dec. 19, 2024

There is no way of counteracting this weapon, which attacks targets at a speed of 10 Mach, or 2.5-3km/s, he said.

From BBC ● Nov. 21, 2024

Thus there is both a steady flow of genes among maize landraces and a force counteracting that flow.

From "1491" by Charles C. Mann

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