noun: (Roman Catholicism, music) A prayer, typically part of a psalm or other portion of the Bible, read or sung at the start of Mass while or immediately after the priest ascends to the altar.
noun: (Christianity, chiefly Protestantism, music) A composition of vocal music sung at the opening of a church service.
noun: (Christianity, chiefly Protestantism, music) An anthem or psalm sung before a Communion service
noun: (obsolete) The action of entering or going in; an entrance.
