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

Even 20 minutes of daily moderate exercise won't counteract the negative health impacts of incessant sitting. —Alayna Alvarez, Axios, 5 Nov. 2024

However, some levodopa medications also contain carbidopa, which can counteract the interaction.4 People using levodopa or levodopa-carbidopa intestinal gel (LCIG) can develop a vitamin B6 deficiency. —Alyssa Hui-Anderson, Verywell Health, 31 Oct. 2024

By consciously focusing on potential gains rather than losses, individuals can counteract their bias toward loss. —Bryce Hoffman, Forbes, 31 Oct. 2024

To do so, this uses a blend of ultra-violet pigments that counteract yellow and brassy tones to ensure your color is always up to your standard in between salon appointments. —Iman Balagam, Vogue, 30 Oct. 2024

Word History

First Known Use

1655, in the meaning defined above

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