Translate react | into French | into German | into Italian | into Spanish Definition of react
verb
[no object] respond or behave in a particular way in response to something:he reacted angrily to the news of his dismissal the market reacted by falling a further 3.1% (
react against)
respond with hostility, opposition, or a contrary course of action to:they reacted against the elite art music of their time (of a person) suffer from adverse physiological effects after ingesting, breathing, or touching a substance:many babies react to soy-based formulas Chemistry &
Physics interact and undergo a chemical or physical change:the sulfur in the coal reacts with the limestone during combustion [with object] Chemistry cause (a substance) to undergo a change by interacting with another substance. Stock Market (of stock prices) fall or rise in reaction to events, developments, etc..