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noun American English pronunciation: fiber /ˈfaɪbər/ 
Word Forms
  1. 1
    [uncountable] the parts of fruit, vegetables, and grains that your body cannot digest (=change into substances it can use). It helps food to pass through your body

    dietary fiber

    high/rich/low in fiber:

    foods that are high in fiber

  2. 2
    [countable] a long thin piece of a natural or artificial substance, similar to a thread or hair in shape

    Coir is a strong material made from coconut fibers.

    1. a.
      [countable/uncountable] a type of cloth or similar material made of fibers
      man-made/synthetic/natural fibers:

      natural fibers such as linen and cotton

      tubes made of carbon fiber

  3. 3
    [countable/uncountable] [usually plural] one of the thin pieces that form the nerves and muscles in your body
    nerve/muscle fibers:

    Messages pass along the nerve fibers.


dark pool

a method of financial trading in which share prices are hidden and not openly available to the public

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bottom gear

the gear that you use for driving a vehicle very slowly

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to post a tweet, usually a negative one, that mentions a person without using the @ sign, so that they will not see the message on their Twitter feed …

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