counteract
verb
coun·ter·act
ˌkau̇n-tər-ˈakt 
counteracted; counteracting; counteracts
: to make ineffective or restrain or neutralize the usually ill effects of by means of an opposite force, action, or influence
a drug used to counteract fatigue
Synonyms
Examples of counteract in a Sentence
The drug will counteract the poison.
this medication will counteract the symptoms but it won't kill the infection
Recent Examples on the Web
While higher costs and catastrophe exposure have led to insurers cutting coverage and rising premiums in Florida, making homes more resilient to extreme weather events could counteract this trend and keep rates stable in the disaster-prone state.
—
Thomas G. Moukawsher, Newsweek, 12 Feb. 2025
Various factors such as melting sea ice and shifts in the subtropical jet stream over the mid-latitudes in the U.S. may counteract each other.
—Dinah Voyles Pulver, USA TODAY, 10 Feb. 2025
The 2022 law, which created the Connecticut Opioid Settlement Advisory Committee, was inspired by model legislation offered up by President Joe Biden’s administration and was meant to ensure that the settlement funds were put to use counteracting the deadly effects of the opioid epidemic.
—Laura Tillman, Hartford Courant, 8 Feb. 2025
Its key trio of lactic acid, glycerin, and urea not only counteracts the look of crepey skin, but also neutralizes any irritation for some soothing relief.
—Jennifer Hussein, Allure, 8 Feb. 2025
See all Example Sentences for counteract 
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Thomas G. Moukawsher, Newsweek, 12 Feb. 2025
Various factors such as melting sea ice and shifts in the subtropical jet stream over the mid-latitudes in the U.S. may counteract each other.
—Dinah Voyles Pulver, USA TODAY, 10 Feb. 2025
The 2022 law, which created the Connecticut Opioid Settlement Advisory Committee, was inspired by model legislation offered up by President Joe Biden’s administration and was meant to ensure that the settlement funds were put to use counteracting the deadly effects of the opioid epidemic.
—Laura Tillman, Hartford Courant, 8 Feb. 2025
Its key trio of lactic acid, glycerin, and urea not only counteracts the look of crepey skin, but also neutralizes any irritation for some soothing relief.
—Jennifer Hussein, Allure, 8 Feb. 2025
See all Example Sentences for counteract
Dictionary Entries Near counteract
Cite this Entry
“Counteract.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/counteract. Accessed 21 Feb. 2025.
Copy CitationKids Definition
counteract
verb
coun·ter·act
ˌkau̇nt-ə-ˈrakt
: to lessen the force, action, or influence of : offset
a drug that counteracts a poison
Medical Definition
counteract
transitive verb
coun·ter·act
ˌkau̇nt-ə-ˈrakt
: to make ineffective or restrain or neutralize the usually ill effects of by an opposite force
vitamin K counteracts the effects of warfarin
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