Definition of react
1 : to exert a reciprocal or counteracting force or influence —often used with on or upon
2 : to change in response to a stimulus
3 : to act in opposition to a force or influence —usually used with against
4 : to move or tend in a reverse direction
5 : to undergo chemical reaction
: to cause to react
Examples of react in a Sentence
When I told her what happened, she reacted with anger.
I didn't expect him to react that way.
The firefighters reacted quickly when they heard the alarm.
He reacted badly to the drug.
Recent Examples of react from the Web
A gentle start in September will allow it time to see how the markets react before committing to a third rate hike in December, the WSJ’s reasoning goes.
But national standards prescribe only one such small sign, not both — so drivers can react faster.
Denver is positioning itself as a smart, balanced, read-and-react team.
Before any of them could react, one monster wave hovered over them and another surged at the bow.
From the shocked to the impressed to the in denial, this is how Twitter is reacting to the Rumi and Sir name rumors:
But union negotiators are said to feel that the new proposal still contains a wide range of rollbacks and have reacted with anger and dismay.
What Rhimes hated even more was how slimming down changed the way people reacted to her.
Smith that noted a second armed suspect was also in the store at the time and the officer, identified as Officer Jamaal Johnson, a 16-year veteran, was reacting quickly to a threat.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'react'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
REACT Defined for English Language Learners
Definition of react for English Language Learners
: to behave or change in a particular way when something happens, is said, etc.
of a chemical substance : to change after coming into contact with another substance
medical : to be affected by a drug, food, etc., in usually a bad way
REACT Defined for Kids
Definition of react for Students
1 : to act or behave in response to something Firefighters reacted quickly to the situation.
2 : to oppose a force or influence Hint: In this sense, react is usually used with against. Workers reacted against unfair treatment.
3 : to go through a chemical reaction Acids react with bases to form salt.
Seen and Heard
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