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

A warm, dry postglacial interval.

A work of art or drama which evokes a particular historical era. / A work which evokes the era in which it was produced, but may not have any other especial features.

(of an astronomic object) The time taken to rotate about its axis relative to the background stars.

rotational period

A relatively brief period when a new leader is given greater leeway with respect to changes he or she wishes to make.

A period during which a new employee is monitored to assess his/her capability.

plural of xerothermic period

plural of period piece

(epidemiology) The time elapsed between an exposure to a pathogenic organism, a chemical or radiation, and the appearance of signs and symptoms.