Period may refer to:

Common uses

  • Period (punctuation)
  • Era, length or span of time
  • Periodization, classifying particular lengths of time into distinct historiographic or artistic periods
  • List of time periods
  • History by period
  • Menstruation, commonly referred to as a "period"

Arts, entertainment, and media

  • Period (music), concept in musical composition
  • Periodic sentence or rhetorical period, concept in grammar and literary style
  • Period drama, dramatic film or television production set in a historical period
  • Period (Another American Lie), 1987 album by B.A.L.L.
  • Period (Kesha album), 2025
  • Period (mixtape), 2018 City Girls mixtape
  • Period, novel in Dennis Cooper's George Miles cycle
  • Periods., comedy film series

Mathematics

  • In a repeating decimal, the length of the repetend
  • Period of a function, length or duration after which a function repeats itself
  • Period (algebraic geometry), numbers that can be expressed as integrals of algebraic differential forms over algebraically defined domains, forming a ring

Science

  • Period (gene), gene in Drosophila involved in regulating circadian rhythm
  • Period (periodic table), horizontal row of the periodic table
  • "Period-" or "per-iod-", chemical prefix where "per" refers to oxidation state and "iod" refers to iodine
  • Unit of time or timeframe
  • Period (geology), subdivision of geologic time
  • Period (physics), the duration of time of one cycle in a repeating event
  • Orbital period, the time needed for one object to complete an orbit around another
  • Rotation period, the time needed for one object to complete a revolution
  • Wavelength, the spatial period of a periodic wave
  • Sentence (linguistics), especially when discussing complex sentences in Latin syntax

Other uses

  • Period (school), block of time allocated for a specific course or other purpose
  • Playing period, a division of playing time in games and sport
  • Period (ice hockey)
  • Accounting period, often shortened to "period" in business, an accounting timeframe analogous to a month
  • Periodt, slang of period used as an interjection

See also

  • . (disambiguation)
  • Duration (disambiguation)
  • Full stop (disambiguation)
  • Periodicity (disambiguation)