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invalidate - definition and synonyms


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verb [transitive] formal invalidate pronunciation in American English /ɪnˈvælɪˌdeɪt/
Word Forms
present tense
present participleinvalidating
past tenseinvalidated
past participleinvalidated
  1. 1
    to make something such as a document, contract, or process no longer legally effective
    Failure to report any changes in your situation may invalidate your insurance policy.
  2. 2
    to prove that an argument or opinion is wrong
    This study invalidates their earlier research.


a course of study which is much shorter than a university course and focuses on the skills you need for a job, especially computer-related skills

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an ancient Roman system of underfloor heating, used to heat houses with hot air; from the Latin 'hypocaustum'

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