in·​ter·​ac·​tion | \ ˌin-tər-ˈak-shən How to pronounce interaction (audio) \

Definition of interaction

: mutual or reciprocal action or influence

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Other Words from interaction

interactional \ ˌin-​tər-​ˈak-​shnəl How to pronounce interactional (audio) , -​shə-​nᵊl \ adjective

Synonyms & Antonyms for interaction


commerce, dealings, intercourse, relation



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Examples of interaction in a Sentence

she guessed from the friendly interaction that they were close to the other parents in the organization

Recent Examples on the Web

But how did the planet lose its moon? Exoplanets can have destructive relationships with their host stars, colliding with them or ultimately being destroyed by an intense interaction. Ashley Strickland, CNN, "This mysterious star could be consuming a stolen exomoon," 17 Sep. 2019 The ultimate goal of such an approach to medication management is to improve efficacy and avoid potentially serious complications and drug interactions., "Community News For The West Hartford Edition," 16 Sep. 2019 The impetus for such interactions, the team writes, may have been seasonal gatherings designed to join communities both nearby and further afield. Meilan Solly, Smithsonian, "Grave Hints at Interaction Between Early Humans Living in Great Lakes, American Southeast," 16 Sep. 2019 There has long been speculation that protons may change in size depending on context, and confirmation of that would lead to a trove of unknown interactions that would upend the particle physics world. Wired, "A Buzzkill Physics Discovery, a Deadly Miracle Drug, and More News," 16 Sep. 2019 Since that interaction, Galvis has remained Damien’s favorite player. Bobby Nightengale,, "Freddy Galvis makes it a special birthday for a young Cincinnati Reds fan," 15 Sep. 2019 Both events are held after-hours to create a calmer library setting and more personalized interaction with presenters. Sam Boyer,, "Church group comes to the rescue and so can you: Whit & Whimsey," 13 Sep. 2019 But the field hockey match sat tied at 0–0 entering the second overtime, leading to an awkward interaction as noon approached. Michael Shapiro,, "Kent State Ends Field Hockey Match in Second Overtime to Start Football Game," 7 Sep. 2019 Baca was charged with the crimes in early 2019, after a patient at the John Muir Medical Center in Walnut Creek alleged Baca groped him during an interaction at the hospital. Nate Gartrell, The Mercury News, "Nursing assistant at East Bay hospital acquitted of sexual assault, burglary," 5 Sep. 2019

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

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First Known Use of interaction

1832, in the meaning defined above

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Statistics for interaction

Last Updated

9 Oct 2019

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Time Traveler for interaction

The first known use of interaction was in 1832

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More Definitions for interaction


in·​ter·​ac·​tion | \ ˌin-tər-ˈak-shən How to pronounce interaction (audio) \

Kids Definition of interaction

1 : the act of talking or doing things with other people Board games encourage interaction.
2 : the action or influence of things on one another interaction of the heart and lungs


in·​ter·​ac·​tion | \ ˌint-ə-ˈrak-shən How to pronounce interaction (audio) \

Medical Definition of interaction

: mutual or reciprocal action or influence interaction of the heart and lungs

Other Words from interaction

interactional \ -​shnəl, -​shən-​ᵊl How to pronounce interactional (audio) \ adjective

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Comments on interaction

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