[in-ter-ak-shuh n]
See more synonyms for interaction on
  1. reciprocal action, effect, or influence.
  2. Physics.
    1. the direct effect that one kind of particle has on another, in particular, in inducing the emission or absorption of one particle by another.
    2. the mathematical expression that specifies the nature and strength of this effect.

Origin of interaction

First recorded in 1825–35; inter- + action
Related formsin·ter·ac·tion·al, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for interaction

synergy, communication, cooperation, intercommunication

Examples from the Web for interaction

Contemporary Examples of interaction

Historical Examples of interaction

British Dictionary definitions for interaction


  1. a mutual or reciprocal action or influence
  2. physics the transfer of energy between elementary particles, between a particle and a field, or between fieldsSee strong interaction, electromagnetic interaction, fundamental interaction, gravitational interaction, weak interaction, electroweak interaction
Derived Formsinteractional, adjective
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for interaction

1812, from inter- + action.

Online Etymology Dictionary, © 2010 Douglas Harper