Here is a explanation of ‘kipparot’ by one of the rabbis on campus. Ive tried to define a few of the terms that he uses:
Slichot: prayers offered to prepare the heart to repent on erev yom kippur (eve of Day of Atonement)
Kipparot: a ceremony symbolizing atonement in which a chicken is waved over head 3 times
Rabbi Karo: wrote one of the definitive commentaries on the Mishnah in the 1500’s.