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react - definition and synonyms


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verb [intransitive] react pronunciation in American English /riˈækt/
Word Forms
present tense
present participlereacting
past tensereacted
past participlereacted
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  1. 1
    to behave in a particular way because of something that is happening around you or something that someone is doing to you

    I wasn’t sure how you would react.

    Workers reacted angrily to the news of more job losses at the factory.

    react by doing something:

    When the parliament formally criticized him, Yeltsin reacted by threatening to close it down.

    react accordingly/appropriately:

    The software enables the computer to interpret messages and react accordingly.

  2. 2
    to become sick when you eat a particular food or take a particular drug
    react to:

    Some children react badly to antibiotics.

  3. 3
    chemistry if a chemical substance reacts with another substance, it changes as they are mixed together
    react with:

    Car emissions react with sunlight to form ozone.

phrasal verbs


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in an online conversation, repeatedly asking a person questions which suggest that you are interested in what they are talking about, but are actually intended to annoy them

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