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 of counteract

• offset
• neutralize
• correct

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

In sportier modes, each wheel can counteract handling forces with up to 2,250 pounds of resisting force. — Lawrence Ulrich, Robb Report, 15 July 2026

Both products add heat protection, but the former helps to counteract that by strengthening the hair simultaneously. — Reece Andavolgyi, InStyle, 13 July 2026

Satellites perform a delicate dance to maintain their orbit, by locking themselves to a speed just fast enough to counteract the downward pull of gravity. — Victor Tangermann, Futurism, 9 July 2026

This ambitious strategy, known as marine cloud brightening (MCB), has been one of several geoengineering strategies contemplated as a way to counteract global warming. — Cody Cottier, Scientific American, 8 July 2026

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