The word "breviary" comes from brevis. This means concise or short. It's a liturgical book of the Latin liturgical rites of the Catholic Church. This book contains prayers, readings, Psalms, notations and hymns.

There are nine rites in the Catholic Church, eight of which are not the Latin (Roman) Rite, and most of those eight rites are Eastern: Byzantine, Armenian, Chaldean, Coptic, Ethiopic, Malabar, Maronite, and Syrian. Each of them has their own proper liturgical calendar.

"Rite" may be used in two ways, one is the Rite of the Church (Latin or Eastern), the other would be the Rite of the Sacrament. There are numerous Rites within the church and each would have its own rite for Baptism, these would include:

Alexandrian liturgical tradition; 2 liturgical rites

Coptic Rite

Ethiopic Rite

Antiochian (Antiochene or West-Syrian) liturgical tradition; 3 liturgical rites

Maronite Rite

(West) Syrian Rite

Syro-Malankara Rite

Armenian Rite; 1 liturgical rite

Armenian Rite

Chaldean or East Syrian liturgical tradition; 2 liturgical rites

Chaldean Rite

Syro-Malabar Rite

Byzantine (Constantinopolitan) liturgical tradition; 1 liturgical rite

Byzantine Rite

Latin (Western) liturgical rites

Actively celebrated:

Roman Rite, whose historical forms are usually classified as follows

Pre-Tridentine Mass (the various pre-1570 forms)

Tridentine Mass (1570-1970 and still authorized in circumstances indicated in the document Summorum Pontificum as an extraordinary form of the Roman Rite)

Mass of Paul VI (1970-present)

Anglican Use (restricted to formerly Anglican congregations)

Ambrosian Rite (Milan, Italy and neighbouring areas)

Aquileian Rite (defunct: northeastern Italy)

Rite of Braga (Braga, Portugal)

Mozarabic Rite (Toledo and Salamanca, Spain)

A liturgical book containing rites and prayers of the Mass, ordinations, etc.

Christus is a Latin equivalent of 'Christ'. It's a masculine noun. It's pronounced 'KREE-stoos' in liturgical Latin, and 'KRIHS-toos' in classical Latin.