tashlik

from The Century Dictionary.

• noun An orthodox Jewish custom of shaking the skirts, on the afternoon of New-Year's day (Rash-ha-shanah), on the shores of a stream, river, or sea. One of the three verses (Micah vii. 18–20) recited at the performance of this custom has the word ve-tashlik, literally, “and thou wilt cast away (our sins),” hence the name.