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radius - definition and synonyms

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noun [countable]     radius pronunciation in British English
Word Forms
pluralradii or radiuses
  1. 1
    maths the distance from the centre of a circle to its edge, or a straight line from the centre to the edge
    1. a.
      a particular distance in all directions from a central point

      All roads within a two-mile radius of the stadium were closed.

  2. 2
    medical the larger outer bone in the lower arm, next to the ulna
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patio diplomacy

high-level diplomats meeting and dining in an informal environment e.g. a party or club

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