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peak - definition and synonyms

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noun [countable]     peak pronunciation in British English
Word Forms
  1. 1
    the time when something is at its highest or greatest level

    The city’s population is about 400,000, down from a peak of 750,000 in the late 1960s.

    The traffic reaches its peak at about 8.30 in the morning.

    1. a.
      the time when someone or something is most successful or powerful
      at your/its peak:

      Sampras was at his peak in the 1990s.

      reach your/its peak:

      The Ottoman Empire reached its peak in the 15th and 16th centuries.

    2. b.
      maths used in mathematics about graphs, waves etc

      The higher the peak, the louder the sound.

  2. 2
    the top of a mountain

    snow-covered peaks

    1. a.
      mainly literary a mountain

      one of the hardest peaks in Europe for climbers

    2. b.
      an object or shape that looks like the top of a mountain
  3. 3
    the flat curved part of a cap that continues beyond the main at the front above your eyes


a lifestyle focussing on simple pleasures such as comfort and cosiness in the home, and spending time with friends and family

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a form of location that involves the underwater detonation of a bomb which causes sound waves that are picked up by ships

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