When?

new moon
the time at which the Moon appears as a narrow waxing crescent
 
Day of Atonement
(Judaism) a solemn and major fast day on the Jewish calendar; 10th of Tishri; its observance is one of the requirements of the Mosaic law
 
study hall
a period of time during the school day that is set aside for study
 
Advent Sunday
the first of the four Sundays during Advent
 
Shrove Tuesday
the last day before Lent
 
Lower Paleolithic
the oldest part of the Paleolithic Age with the emergence of the hand ax; ended about 120,000 years ago
 
Bronze Age
(archeology) a period between the Stone and Iron Ages, characterized by the manufacture and use of bronze tools and weapons
 
Id al-Fitr
a Muslim day of feasting at the end of Ramadan
 
Feast of Dormition
celebration in the Eastern Orthodox Church of the Virgin Mary's being taken up into heaven when her earthly life ended; corresponds to the Assumption in the Roman Catholic Church and is also celebrated on August 15th
 
playtime
time for play or diversion
 
Shrovetide
immediately preceding Lent
 
springtime
the season of growth
 
Fast of the Firstborn
(Judaism) a minor fast day on Nissan 14 that is observed only by firstborn males; it is observed on the day before Passover
 
exhibition season
the time before the regular games begin when football or baseball teams play practice games
 
regency
the period of time during which a regent governs
 
Saint Martin's summer
a period of unusually warm weather in the autumn
 
Reconstruction Period
the period after the American Civil War when the southern states were reorganized and reintegrated into the Union; 1865-1877
 
quatercentennial
the 400th anniversary (or the celebration of it)
 
eld
a time of life (usually defined in years) at which some particular qualification or power arises
 
second
an indefinitely short time
 
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