Period may refer to: Common uses Era, a length or span of time Full stop (or period), a punctuation mark Menstruation, commonly referred to as a "period" Arts, entertainment, and media Period (music), a concept in musical composition Periodic sentence (or rhetorical period), a concept in grammar and literary style. Period, a descriptor for a historical or period drama Period, a timeframe in which a particular style of antique furniture or some other work of art was produced, such as the "Edwardian period" Period (Another American Lie), a 1987 album by B.A.L.L. Period (mixtape), a 2018 mixtape by City Girls Period, the final book in Dennis Cooper's George Miles cycle of novels 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), a gene in Drosophila involved in regulating circadian rhythm Period (periodic table), a horizontal row of the periodic table "Period-" or "per-iod-", in some chemical compounds, "per" refers to oxidation state, and "iod" refers to the compound containing iodine Unit of time or timeframe Period (geology), a 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), a class meeting time in schools Period (ice hockey), a division of play in an ice hockey game Accounting period, often shortened to "period" in business, an accounting timeframe analogous to a month See also Duration (disambiguation) Full stop (disambiguation) Periodicity (disambiguation) Periodization List of time periods History by period