counteract

play
verb coun·ter·act \ ˌkau̇n-tər-ˈakt \

Definition of counteract

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

play \ˌkau̇n-tər-ˈak-shən\ noun

counteractive

play \ˌkau̇n-tər-ˈak-tiv\ adjective

Examples of counteract in a Sentence

  1. The drug will counteract the poison.

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

Recent Examples of counteract from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'counteract.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of counteract

1655


COUNTERACT Defined for English Language Learners

counteract

play
verb

Definition of counteract for English Language Learners

  • : act against (something) : to cause (something) to have less of an effect or to have no effect at all


COUNTERACT Defined for Kids

counteract

play
verb coun·ter·act \ ˌkau̇n-tər-ˈakt \

Definition of counteract for Students

counteracted; counteracting
:to make (something) have less of an effect or no effect at all
  • The antidote counteracts the poison.

Medical Dictionary

counteract

play
transitive verb coun·ter·act \ ˌkau̇nt-ə-ˈrakt \

medical Definition of counteract

:to make ineffective or restrain or neutralize the usually ill effects of by an opposite force
  • vitamin K counteracts the effects of warfarin

counteraction

play \-ˈrak-shən\ noun


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