Mass n.
 1. R. C. Ch. The sacrifice in the sacrament of the Eucharist, or the consecration and oblation of the host.
 2. Mus. The portions of the Mass usually set to music, considered as a musical composition; -- namely, the Kyrie, the Gloria, the Credo, the Sanctus, and the Agnus Dei, besides sometimes an Offertory and the Benedictus.
 Canon of the Mass. See Canon.
 High Mass, Mass with incense, music, the assistance of a deacon, subdeacon, etc.
 Low Mass, Mass which is said by the priest throughout, without music.
 Mass bell, the sanctus bell. See Sanctus.
 Mass book, the missal or Roman Catholic service book.