a Jewish high holy day observed on the 10th day of the month of Tishri by abstinence from food and drink and by the daylong recitation of prayers of repentance in the synagogue.
Yom Kip·pur (yôm' kĭp'ər, yōm', yŏm', yôm' kē-pŏŏr') n.
Judaism A holy day observed on the tenth day of Tishri and marked by fasting and prayer for the atonement of sins. Also called Day of Atonement.
[Hebrew yôm kippûr : yôm, day; see ywm in Semitic roots + kippûr, atonement (from kippēr, to cover, atone; see kpr1 in Semitic roots).]