religious ceremony, religious ritual - a ceremony having religious meaning

vigil, watch - a devotional watch (especially on the eve of a religious festival)

last rites - rites performed in connection with a death or burial

orgy - secret rite in the cults of ancient Greek or Roman deities involving singing and dancing and drinking and sexual activity

circumcision - the act of circumcising performed on males eight days after birth as a Jewish and Muslim religious rite

liturgy - a rite or body of rites prescribed for public worship

office - a religious rite or service prescribed by ecclesiastical authorities; "the offices of the mass"