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triangle - definition and synonyms

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noun [countable]     triangle pronunciation in British English
Word Forms
  1. 1
    maths a flat shape that has three straight sides and three angles
    1. a.
      something that has the shape of a triangle

      a triangle of land

  2. 2
    Sound effect a simple musical instrument consisting of a metal triangle that you hit with a metal bar. The triangle is a percussion instrument.
  3. 3
    a situation in which three people or groups are involved, although they have different opinions, ideas, or aims

    a love triangle


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