interaction

noun

in·​ter·​ac·​tion ˌin-tər-ˈak-shən 

: mutual or reciprocal action or influence

interactional

ˌin-tər-ˈak-sh(ə-)nəl 

adjective

Synonyms of interaction

• relation
• intercourse
• dealings

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

The researchers said these atomic-scale interactions are difficult to capture accurately using classical approximation methods alone. — Neetika Walter, Interesting Engineering, 8 July 2026

The investigator did not detail what occurred during that interaction or if members of Kirk’s security team were present. — Hannah Schoenbaum, Los Angeles Times, 8 July 2026

To this end, rather than automate the booking experience, Travel Business Class is going the opposite direction; putting emphasis on human-to-human interaction. — William Jones, USA Today, 8 July 2026

And greater convenience reduced the need for many small daily interactions, from running errands to attending meetings to asking simple questions in person. — Kim Meninger, Forbes.com, 8 July 2026

Word History

First Known Use

1832, in the meaning defined above

Rhymes for interaction

• benefaction
• counteraction
• liquefaction
• putrefaction
• rarefaction
• satisfaction
• stupefaction
• tumefaction
• abstraction
• attraction
• compaction
• contraction

Kids Definition

interaction

noun

in·​ter·​ac·​tion ˌint-ə-ˈrak-shən 

: the action or influence of people, groups, or things on one another

interactional

-shnəl 

-shən-ᵊl

adjective

Medical Definition

interaction

noun

in·​ter·​ac·​tion ˌint-ə-ˈrak-shən 

: mutual or reciprocal action or influence

interaction of the heart and lungs

interactional

-shnəl, -shən-ᵊl 

adjective