(astronomy) Having an orbital period of less than 200 years, especially said of comets

(music) The musical period of time following the Renaissance, extending roughly between 1600-1750.

The period of time during which ovulation takes place. / The period of time between ovulations.

(physics) A characteristic of the transition of a system or process from regular motion to chaos, in which the period of one of its parameters is seen to double.

The 45-year reign of Emperor Meiji (1868-1912). During this time, Japan started its modernization and rose to world power status.

(idiomatic) A length of time during which rules or penalties are waived or deferred.

a school period in which a student has free time, i.e., is not enrolled in a class.

plural of zero period

plural of notice period

plural of menstrual period