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bug - definition and synonyms


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noun bug pronunciation in British English /bʌɡ/
Word Forms
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  1. 1
    [countable] informal an infectious but usually minor illness
    a flu bug
    get/pick up a bug (=develop an illness): You must have picked up a bug on holiday.
  2. 2
    [countable] computing a minor fault in a computer system or in a computer program
    The new program still has some bugs in it.
  3. 3
    [singular] informal a sudden strong enthusiasm for doing something
    be bitten by the travel/fitness/cooking etc bug (=to suddenly become enthusiastic about it): I’d been bitten by the back-packing bug.
  4. 4
    [countable] a small piece of electronic equipment used for secretly listening to what people are saying
    Detectives had planted (=put) a bug in his hotel room.
    Synonyms and related words
  5. 5
    [countable] informal an insect
    There were bugs crawling all over the kitchen floor.


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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