counteract

verb

coun·​ter·​act ˌkau̇n-tər-ˈakt 

counteracted; counteracting; counteracts

transitive verb

: 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

counteraction

ˌkau̇n-tər-ˈak-shən 

noun

counteractive

ˌkau̇n-tər-ˈak-tiv 

adjective

Synonyms

• annul
• cancel (out)
• compensate (for)
• correct
• counterbalance
• counterpoise
• make up (for)
• negative
• neutralize
• offset

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 is partly to counteract the soaring unemployment across the continent. —Chris Barbin, Forbes.com, 17 June 2025

However, this positive impact isn’t enough to counteract the negative health effects of alcohol.4 Who Should Not Drink? —Kelly Burch, Verywell Health, 16 June 2025

Modern facelift surgeons lift in a mostly vertical direction to counteract the effects of gravity and time. —Jolene Edgar, Allure, 10 June 2025

What parents can do to counteract this influence is to expose them to other career paths. —Melissa Willets, Parents, 6 June 2025

Word History

First Known Use

1655, in the meaning defined above

Rhymes for counteract

• artefact
• artifact
• inexact
• interact
• noncontact
• reenact
• subcontract
• abstract
• attacked
• attract
• contact
• contract

Kids Definition

counteract

verb

coun·​ter·​act ˌkau̇nt-ə-ˈrakt 

: to lessen the force, action, or influence of : offset

a drug that counteracts a poison

counteraction

-ˈrak-shən 

noun

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

counteraction

-ˈrak-shən 

noun