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slack - definition and synonyms


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adjective slack pronunciation in American English /slæk/
Word Forms
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  1. 1
    loose and not pulled tight
    The fence consisted of two slack strands of barbed wire.
    The rope suddenly went slack.
    Her muscles felt slack.
  2. 2
    not taking enough care to make sure that something is done well
    slack safety standards
    She’d been brought in to clean up slack working habits among the employees.
  3. 3
    not as busy or successful as usual in business
    Business is usually slack in the winter.
    Demand for the product is slack.

derived word


noun [uncountable]


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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a stupid person

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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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