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harden - definition and synonyms


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verb harden pronunciation in American English /ˈhɑrd(ə)n/
Word Forms
present tense
present participlehardening
past tensehardened
past participlehardened

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  1. 1
    [intransitive/transitive] to become hard or firm, or to make something hard or firm

    This additive hardens the cement in an hour.

    The bread will harden if you don’t cover it.

  2. 2
    [transitive] mainly literary to make someone become less affected or upset by unpleasant things so that they show less kindness or sympathy to other people
    harden someone to something:

    Years of reporting on wars hardened them to human suffering.

    1. a.
  3. 3
    [intransitive/transitive] to become strong, to make someone or something strong

    The soldiers have been hardened by months in the field.

  4. 4
    [intransitive/transitive] if you harden your attitude, or if it hardens, you refuse to change it

    Forsyth appeared to have hardened his line on (=his attitude toward) Europe.

derived word


noun [singular/uncountable]

She has hardening of the arteries.

a hardening of opinion against the treaty


sea lion

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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an electric skateboard

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