The meaning of INTERACTION is mutual or reciprocal action or influence. How to use interaction in a sentence.

interaction noun [C, U] (THINGS) the way that two or more things combine and have an effect on each other

(of two or more people, things etc) to act, or have some effect, on each other.

Definition of interaction noun in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

Interaction, or an interaction, of substances occurs when the substances affect each other's behavior or action. One possible drug interaction can involve the drugs working together to …

Established in 1984, InterAction is the leading alliance of NGOs and partners in the United States. With a focus on serving the world’s impoverished and vulnerable populations, our organization …

in•ter•ac•tion, n. [uncountable] social interaction between men and women. [countable] day-to-day interactions. in•ter•ac•tive, adj.: Interactive video lets the user decide what to see on the screen.

A conversation or exchange between people. I enjoyed the interaction with a bunch of like-minded people.

Jan 20, 2026 · interaction (countable and uncountable, plural interactions) The situation or occurrence in which two or more objects or events act upon one another to produce a new …

If you interact with someone — by talking, looking, sharing, or engaging in any kind of action that involves the two of you — you can be said to have had an interaction with that person.