re‧act S3 W3 [intransitive]


to behave in a particular way or show a particular emotion because of something that has happened or been said [↪ respond]
react to
How did Wilson react to your idea?
He reacted angrily to the suggestion that he had lied.
She reacted very badly (=was very upset) when her parents split up.
You have to react quickly to circumstances.
react by doing something
The government reacted by declaring all strikes illegal.


technicalHC if a chemical substance reacts, it changes when it is mixed with another chemical substance
react with
The calcium reacts with sulphur in the atmosphere.


if prices or financial markets react to something that happens, they increase or decrease in value because of it
react to
Oil prices reacted sharply (=reacted a lot) to news of the crisis in the Middle East.
The market reacted favourably to the announcement.

become ill

MI to become ill when a chemical or drug goes into your body, or when you eat a particular kind of food [↪ respond]
react to
Quite a lot of children react badly to antibiotics.

react against something

phrasal verb
to show that you dislike someone else's ideas or ways of doing something, by deliberately doing the opposite:
He reacted strongly against his religious upbringing.

Dictionary results for "react"
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