counteract

1 of 2

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

counteraction

2 of 2

noun

coun·​ter·​ac·​tion ¦kau̇n-tər-¦ak-shən 

plural -s

1

: contrary action : opposition, resistance

scheming counteraction

2

: act or action of counteracting : a counteracting agency

the counteraction of centripetal forces on centrifugal tendencies

Synonyms of counteract

Verb

• offset
• neutralize
• correct

Examples of counteract in a Sentence

Verb

The drug will counteract the poison.

this medication will counteract the symptoms but it won't kill the infection

Recent Examples on the Web

Verb

Additionally, doctors often recommend over-the-counter antihistamines such as Benadryl to counteract histamine released by the immune system. — Maggie O'Neill, Verywell Health, 29 July 2026

Unlike other restaurant chains that have relied on higher prices to counteract declining customer traffic, Cheesecake Factory has reported steady traffic growth. — Ty Roush, Forbes.com, 29 July 2026

The script brilliantly lays that out to counteract some of the hugeness of her character. — David Canfield, HollywoodReporter, 28 July 2026

Bent-over rows may be especially helpful for counteracting the forward head and rounded shoulder positioning that can result from frequent cell phone use. — Danielle Zickl, Health, 27 July 2026

Word History

First Known Use

Verb

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