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gas - definition and synonyms


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noun gas pronunciation in American English /ɡæs/
Word Forms
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  1. 1
    [uncountable] American liquid fuel that is used for producing power in the engines of cars. The British word is petrol
    get gas:

    We need to get some gas before we leave town.

  2. 2
    [countable/uncountable] science a substance such as air that is neither a solid nor a liquid

    regulations to cut the emissions of gases such as carbon dioxide

    They detected high levels of radon gas in the building.

    Synonyms and related words
    1. a.
      [uncountable] a gas burned as fuel, for example to heat your house or cook food

      She couldn’t pay her gas bill.

      Can you smell gas?

    2. b.
      [uncountable] a gas used for harming or killing people, or for affecting their behavior
      Synonyms and related words
    3. c.
      [uncountable] a gas produced inside your body by your stomach. The usual British word is wind. If you pass gas, air comes out of your bottom.
    4. d.
      [uncountable] a gas given to people before an operation to make them sleep, or during medical treatment so that they will feel less pain


a title used before a man or woman's name as a gender-neutral alternative to Mr, Ms, etc

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another way of saying congratulations, or that something/someone looks nice or fascinating

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