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

Wall Street now anticipates the Fed will raise its key interest rate at least once by year’s end in a bid to counteract the stronger price growth. — Rob Wile, NBC news, 25 June 2026

Experts said the strategy is a simple, sustainable way to counteract a sedentary lifestyle and support overall health. — Allison Forsyth, Health, 30 June 2026

Evaporation is a phase change that counteracts warming temperatures and raises humidity in the air. — Trey Fulbright, CBS News, 1 July 2026

Some sunscreens only exacerbate existing redness and inflammation, but EltaMD’s is not only sensitive skin-friendly, but the green tint counteracts any naturally-occurring redness in the skin. — Gina Vaynshteyn, StyleCaster, 23 June 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