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balloon - definition and synonyms


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verb [intransitive] balloon pronunciation in British English /bəˈluːn/
Word Forms
present tense
present participleballooning
past tenseballooned
past participleballooned
  1. 1
    to become larger and rounder in shape
    Her coat ballooned round her in the wind.
    Synonyms and related words
  2. 2
    to increase very quickly in amount or degree
    Our expenses had ballooned.
    Within weeks, the fighting had ballooned into full-scale war.


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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