react
verb
re·act rē-ˈakt 
reacted; reacting; reacts
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
Synonyms
- reply
- respond
See all Synonyms & Antonyms 
Example Sentences
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 on the Web Because Apple is much more likely to notice and react quickly to problems in its own software and apps than third-party games. 
Matthew Humphries, PCMAG, 16 Sep. 2022 The other members of the association were hesitant at first, Frie said, and unsure of how the community would react. Madeline Heim, Journal Sentinel, 15 Sep. 2022 Now, columnist Mike Bianchi and Knights beat reporter Jason Beede recap UCF’s loss against Louisville, react to Nebraska firing coach Scott Frost and preview this week’s game at FAU. Charles King, Orlando Sentinel, 13 Sep. 2022 Moreover, the Consumer Price Index data show that inflation is spreading as a wider variety of businesses react to higher wages and brace for their costs to keep rising. Larry Edelman, BostonGlobe.com, 13 Sep. 2022 Regardless of the game's outcome, watching Peyton, Eli and Shannon react to the ending in real-time showed the genius of the ManningCast format. Matthew Vantryon, USA TODAY, 13 Sep. 2022 Two measure the output of each drive unit, two measure and react to external (ambient) noise and two offer enhanced voice rendition and noise suppression. Robert Ross, Robb Report, 9 Sep. 2022 More painting and etching events could follow depending on how residents — and catalytic converter thieves — react to the deterrents, said Waguespack, who bought the etching kits that will be used Sunday. Jake Sheridan, Chicago Tribune, 9 Sep. 2022 Some researchers even hypothesize that empaths have hyper-responsive mirror neurons, which react when another person’s behavior is observed. Arthur C. Brooks, The Atlantic, 8 Sep. 2022 See More
Matthew Humphries, PCMAG, 16 Sep. 2022 The other members of the association were hesitant at first, Frie said, and unsure of how the community would react. Madeline Heim, Journal Sentinel, 15 Sep. 2022 Now, columnist Mike Bianchi and Knights beat reporter Jason Beede recap UCF’s loss against Louisville, react to Nebraska firing coach Scott Frost and preview this week’s game at FAU. Charles King, Orlando Sentinel, 13 Sep. 2022 Moreover, the Consumer Price Index data show that inflation is spreading as a wider variety of businesses react to higher wages and brace for their costs to keep rising. Larry Edelman, BostonGlobe.com, 13 Sep. 2022 Regardless of the game's outcome, watching Peyton, Eli and Shannon react to the ending in real-time showed the genius of the ManningCast format. Matthew Vantryon, USA TODAY, 13 Sep. 2022 Two measure the output of each drive unit, two measure and react to external (ambient) noise and two offer enhanced voice rendition and noise suppression. Robert Ross, Robb Report, 9 Sep. 2022 More painting and etching events could follow depending on how residents — and catalytic converter thieves — react to the deterrents, said Waguespack, who bought the etching kits that will be used Sunday. Jake Sheridan, Chicago Tribune, 9 Sep. 2022 Some researchers even hypothesize that empaths have hyper-responsive mirror neurons, which react when another person’s behavior is observed. Arthur C. Brooks, The Atlantic, 8 Sep. 2022 See More Word History
Etymology
New Latin reactus, past participle of reagere, from Latin re- + agere to act — more at agent
First Known Use
1644, in the meaning defined at intransitive sense 1
Phrases Containing react
Kids Definition
react
verb
re·act rē-ˈakt
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.
Medical Definition
react
intransitive verb
re·act rē-ˈakt
1
: to respond to a stimulus
2
: to undergo chemical reaction
transitive verb
: to cause to react
reacting
verb
as in responding
to act or behave in response (as to a stimulus or influence) it was my first touchdown, and I didn't know how to react to the cheers of the crowd Synonyms & Similar Words
Relevance
- responding
- replying
- answering
- returning
- retaliating
- reading
- interpreting
- understanding
- managing
- handling
- construing
- negotiating
- taking
- coping (with)
- grappling (with)
- contending (with)
Antonyms & Near Antonyms
- acting
- behaving
- causing
- affecting
- drawing
- effecting