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iron - definition and synonyms


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adjective iron pronunciation in American English /ˈaɪrn/
  1. 1
    made of iron
    huge iron gates
  2. 2
    very strong, strict, or severe
    The whole region was still in the iron grip of winter.
    iron fist/hand (=complete control): For almost 50 years, Hoover ran the FBI with an iron fist.
    1. a.
      very determined
      She possesses an iron will and a sense of purpose.


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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