When?

lactation
the period following birth during which milk is secreted
 
Corpus Christi
Thursday after Trinity Sunday; first celebrated in 1246
 
Olympiad
one of the four-year intervals between Olympic Games; used to reckon time in ancient Greece for twelve centuries beginning in 776 BC
 
Commonwealth Day
British, anniversary of Queen Victoria's birth
 
dry season
one of the two seasons in tropical climates
 
wedding anniversary
the anniversary of the day on which you were married (or the celebration of it)
 
puerperium
time period following childbirth when the mother's uterus shrinks and the other functional and anatomic changes of pregnancy are resolved
 
twentieth century
the century from 1901 to 2000
 
go
a time period for working (after which you will be relieved by someone else)
 
mid-February
the middle part of February
 
afterlife
life after death
 
Feast of Sacrifice
the 10th day of Dhu'l-Hijja; all Muslims attend a service in the mosques and those who are not pilgrims perform a ritual slaughter of a sheep (commemorating God's ransom of Abraham's son from sacrifice) and give at least a third of the meat to charity
 
Walpurgis Night
eve of May Day
 
Fast of Tammuz
(Judaism) a minor fast day on Tammuz 17 when the walls of Jerusalem were breached
 
Jewish calendar month
a month in the Jewish calendar
 
Reconstruction Period
the period after the American Civil War when the southern states were reorganized and reintegrated into the Union; 1865-1877
 
name day
the feast day of a saint whose name one bears
 
quattrocento
the 15th century in Italian art and literature
 
iron age
(classical mythology) the last and worst age of the world
 
Tishri
the first month of the civil year; the seventh month of the ecclesiastical year in the Jewish calendar (in September and October)
 
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