a punctuation mark (.) placed at the end of a declarative sentence to indicate a full stop or after abbreviations | darkness |
the monthly discharge of blood from the uterus of nonpregnant women from puberty to menopause | the time after sunset and before sunrise while it is dark outside |
an amount of time | a period of ignorance or backwardness or gloom |
the interval taken to complete one cycle of a regularly repeating phenomenon | the dark part of the diurnal cycle considered a time unit |
a unit of geological time during which a system of rocks formed | the time between sunset and midnight |
the end or completion of something | the period spent sleeping |
(ice hockey) one of three divisions into which play is divided in hockey games | a shortening of nightfall |