General English

General Science

  • noun the highest point of something



  • noun a highest point, such as the highest point in a trading cycle or the highest point of customer demand for a service


  • The maximum instantaneous value of a voltage, current, signal, or other quantity.
  • The maximum instantaneous absolute value of the displacement from a reference position, such as zero, for a voltage, current, signal, or other quantity. When referring to a wave or other periodic phenomenon, also called amplitude.
  • The peak (1), or peak (2) for a given time interval.

Information & Library Science

  • adjective relating to the highest point or maximum value of a variable


  • noun a moment when something is at its worst, best, etc.


  • the point at which a wine has aged correctly and is at its best in terms of flavour and taste. This is very subjective.

Origin & History of “peak”

Peak seems to come ultimately from the noun pick ‘pointed implement’ (as in toothpick). From this in the 15th century was formed an adjective picked ‘pointed’, which survived dialectally into the 19th century (S H A Hervey noted in the Wedmore Chronicle 1887 ‘Children still use ‘picked’ of a pencil with a good point to it’). It had a variant form peaked, from which peak appears to have been derived as a back-formation. The adjective peaky ‘sickly’ (19th c.), incidentally, is not etymologically related. It comes from a now little used verb peak ‘become sickly or pale’ (16th c.), whose origins are unknown.