The word canticle from the Latin canticulum, a “little song.” As a technical liturgical term, it is used to designate one of the small body of texts that have been traditionally been used in the daily worship of the Church. Almost all of these texts are taken from the Scriptures, and most from outside the Psalter.
Venite exultemus Domino
In the Book of Common Prayer, the first canticle appointed is the Venite exultemus Domino (often called simply the Venite): which begins “O come let us sing unto the Lord.” It is sung at the beginning of Morning Prayer, before the readings — or chanting — from the Psalter, the Old Testament, and the New Testament. It is known as an Invitatory Psalm, as most of its text is taken from Psalm 95 and it serves to invite us into the sequence of readings and prayer. The other canticles are — in both Morning and Evening Prayer — placed as sung responses to our reception of the Biblical texts.
Plainchant setting of the Venite
Te Deum laudamus
Anglican chant setting