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
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
This force pushes outward, counteracting the inward pull of gravity.
—
Rupendra Brahambhatt, Interesting Engineering, 4 Apr. 2026
That's when small amounts of liquid hydrogen and liquid oxygen are continuously added to tanks in order to counteract natural evaporation.
—Miles Doran, CBS News, 1 Apr. 2026
The findings suggest that, if used correctly, AI chatbots could counteract polarization.
—Jeremy Kahn, Fortune, 31 Mar. 2026
Their schedule includes a few more technology demonstrations, a small trajectory correction burn, and trying on their orthostatic intolerance garments — compression clothing worn after landing to help counteract the effects on the body after returning from a microgravity environment.
—Josh Dinner, Space.com, 31 Mar. 2026
See All Example Sentences for counteract
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Rupendra Brahambhatt, Interesting Engineering, 4 Apr. 2026
That's when small amounts of liquid hydrogen and liquid oxygen are continuously added to tanks in order to counteract natural evaporation.
—Miles Doran, CBS News, 1 Apr. 2026
The findings suggest that, if used correctly, AI chatbots could counteract polarization.
—Jeremy Kahn, Fortune, 31 Mar. 2026
Their schedule includes a few more technology demonstrations, a small trajectory correction burn, and trying on their orthostatic intolerance garments — compression clothing worn after landing to help counteract the effects on the body after returning from a microgravity environment.
—Josh Dinner, Space.com, 31 Mar. 2026
See All Example Sentences for counteract
Cite this Entry
“Counteract.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/counteract. Accessed 7 Apr. 2026.
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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