Kol Nidre

(kōl nē′drā, nid′rə; Heb kō̂l′nē drā′)

the prayer declaring a release from religious vows and obligations that were made unintentionally or under duress: it is recited in synagogues at the opening of Yom Kippur eve services
the traditional music to which this is sung

Origin: Heb-Aram kol-nidre, all (our) vows: opening words of prayer < Aram kol, all + nidre, vows, pl. of neder, vow < root ndr, to vow

See Kol Nidre in American Heritage Dictionary 4

noun
Judaism

An opening prayer recited on the eve of Yom Kippur, retroactively or preemptively declaring the annulment of all personal vows made to God in the previous or following year.
The melody to which such a prayer is chanted.

Origin:

Origin: Aramaic kol nidrê, all vows (the opening words of the prayer)

Origin: : kol, all; see kll in Semitic roots

Origin: + nidrê

Origin: , pl. bound form of nidrā, vow (from nədar, to vow; see nḏr in Semitic roots)