plural of ovulatory period

plural of critical period

(psychology, biology) A maturational stage in the lifespan of an organism during which the nervous system is especially sensitive to certain environmental stimuli.

(historical) The history of Japan covering the years from AD 710 to 794. Empress Gemmei established the capital of Heijō-kyō (present-day Nara).

Sexual intercourse during menstruation.

(music) the musical period of time following the Baroque period and preceding the Romantic period, spanning c.1750-c.1820.

plural of periodic function

(music) the musical period of time following the Classical period falling between about 1820 and the start of the twentieth century.

(education) A high school class that is offered early in the morning, before the scheduled start of the school day.

Pain felt in the abdomen during menstruation.