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

Above some critical energy threshold, interactions between those photons and a cosmic ray will be energetic enough that additional particles, like pions, will spontaneously be created. —Big Think, 30 Jan. 2026

Everyday people have in recent weeks fanned out across the city to document protests and film tense interactions with federal immigration officers. —Maggie Vespa, NBC news, 30 Jan. 2026

The zones will create space businesses can utilize for outdoor cafe seating, merchandise display racks and direct interaction with pedestrians. —Alex Driggars, Austin American Statesman, 30 Jan. 2026

Since the start, crypto has been a type of currency rooted in online transactions, interactions, and communication. —William Jones, Ascend Agency, 30 Jan. 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