What is "yom kippur"

Yom Kippur \Yom` Kip*pur"\ (y[=o]m`k[i^]*p[oo^]r", y[aum]m`k[i^]*p[oo^]r"), [Heb. y[=o]m kipp[=u]r, day of atonement.] (Jewish Antiq.) the only fast day of the Mosaic ritual, celebrated on the tenth day of the seventh month (Tishri), according to the rites described in Leviticus xvi. Also called Day of Atonement.

Atonement \A*tone"ment\, n.

1. (Literally, a setting at one.) Reconciliation; restoration of friendly relations; agreement; concord. [Archaic]

   By whom we have now received the atonement.
   --Rom. v. 11.

   He desires to make atonement Betwixt the Duke of Gloucester and your brothers.
   --Shak.

2. Satisfaction or reparation made by giving an equivalent for an injury, or by doing of suffering that which will be received in satisfaction for an offense or injury; expiation; amends; -- with for. Specifically, in theology: The expiation of sin made by the obedience, personal suffering, and death of Christ.

   When a man has been guilty of any vice, the best atonement be can make for it is, to warn others.
   --Spectator.

   The Phocians behaved with, so much gallantry, that they were thought to have made a sufficient atonement for their former offense.
   --Potter.

   Day of Atonement (Jewish Antiq.), the only fast day of the Mosaic ritual, celebrated on the tenth day of the seventh month (Tishri), according to the rites described in Leviticus xvi. Also called Yom Kippur.

Jewish holiday, 1854, from Mishnaic Hebrew yom kippur (in Biblical Hebrew, yom kippurim), literally "day of atonement," from yom "day" + kippur "atonement, expiation."

Yom Kippur (; , , or ), also known as the Day of Atonement, is the holiest day of the year in Judaism. Its central themes are atonement and repentance. Jewish people traditionally observe this holy day with an approximate 25-hour period of fasting and intensive prayer, often spending most of the day in synagogue services.