react

play

verb re·act \rē-ˈakt\

Definition of react

intransitive verb
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
transitive verb
: to cause to react

See react defined for English-language learners

See react defined for kids

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.

— alan murray, Fortune, "CEO Daily: Wednesday, 5th July", 5 July 2017
But national standards prescribe only one such small sign, not both — so drivers can react faster.

— mike lindblom, The Seattle Times, "Judge tosses speeding ticket in school zone over wordy city sign", 4 July 2017
Denver is positioning itself as a smart, balanced, read-and-react team.

— rob mahoney, SI.com, "Grades: Paul Millsap Is The Star Denver Has Long Been Chasing", 3 July 2017
Before any of them could react, one monster wave hovered over them and another surged at the bow.

— Alaska Dispatch News, "Deadly winds of Skilak Lake: A family struggles to survive", 1 July 2017
From the shocked to the impressed to the in denial, this is how Twitter is reacting to the Rumi and Sir name rumors:

— lauren alexis fisher, Harper's BAZAAR, "Twitter Has Some Mixed Feelings About The Names of Beyoncé's Twins", 30 June 2017
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.

— jonathan handel, The Hollywood Reporter, "SAG-AFTRA Deal Elusive as Midnight Expiration, Strike Threat Loom", 30 June 2017
What Rhimes hated even more was how slimming down changed the way people reacted to her.

— anthea levi, Health.com, "Shonda Rhimes Wrote the Realest Essay About Her 150-Pound Weight Loss", 29 June 2017
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.

— kevin rector, baltimoresun.com, "Man shot by Baltimore police in Curtis Bay lifted gun at officer first, body camera footage shows", 29 June 2017

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.

Origin and Etymology of react

New Latin reactus, past participle of reagere, from Latin re- + agere to act — more at agent

NEW!

First Known Use: 1644

See Words from the same year

REACT Defined for English Language Learners

react

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verb

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

react

play

verb re·act \rē-ˈakt\

Definition of react for Students

reacted

;

reacting

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.