Nouns

(n)time period, period of time, periodan amount of time“a time period of 30 years”, “hastened the period of time of his recovery”, “Picasso's blue period”
(n)periodthe interval taken to complete one cycle of a regularly repeating phenomenon
(n)period(ice hockey) one of three divisions into which play is divided in hockey games
(n)period, geological perioda unit of geological time during which a system of rocks formed“ganoid fishes swarmed during the earlier geological periods”
(n)periodthe end or completion of something“death put a period to his endeavors”, “a change soon put a period to my tranquility”
(n)menstruation, menses, menstruum, catamenia, period, flowthe monthly discharge of blood from the uterus of nonpregnant women from puberty to menopause“the women were sickly and subject to excessive menstruation”, “a woman does not take the gout unless her menses be stopped” (Hippocrates), “the semen begins to appear in males and to be emitted at the same time of life that the catamenia begin to flow in females” (Aristotle)
(n)period, point, full stop, stop, full pointa punctuation mark (‘.’) placed at the end of a declarative sentence to indicate a full stop or after abbreviations“in England they call a period a ‘stop’”