seliha

from The Century Dictionary.

• noun Among the Jews, a collection of penitential prayers forming a prayer-book for fast-days, that is, for the week preceding the Jewish New Year, the ten days between New Year's Day and the Day of Atonement, etc. Most of the poems and prayers included under this name have been composed by medieval gaonim (see gaon) and Sephardi rabbis. The selihot are acrostically arranged, many containing not only the alphabet but also the names of the composer and his father.