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ill - definition and synonyms

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adjective     ill pronunciation in American English
Word Forms
  1. 1
    not healthy, because of a medical condition or an injury

    He’s been ill for a couple of weeks.

    She was too ill to travel.

    terminally ill (=going to die because of an illness)

    seriously/critically ill:

    Her husband is seriously ill in the hospital.

    fall ill /be taken ill (=become ill):

    She was unlucky enough to fall ill on vacation.

    ill with:

    Sarah was seriously ill with a fever.

    See also sick
  2. 2
    [only before noun] formal bad, or harmful

    Their defeat was mainly due to their ill-discipline.

    The fish didn’t taste fresh, but we suffered no ill effects.

    ill temper/humor:

    Bouts of ill temper punctuated the match.



a lifestyle focussing on simple pleasures such as comfort and cosiness in the home, and spending time with friends and family

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a form of location that involves the underwater detonation of a bomb which causes sound waves that are picked up by ships

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