Incipit
The opening phrase or word of a text. The term is from the Latin, “it begins.” It may refer to the opening words of the text of a psalm or to the introductory words of a medieval manuscript or early printed book. The incipit may also serve as the title of the text. The BCP publishes the Latin incipit for all psalms and Prayer Book canticles. For example, Ps 133 is published with its incipit, Ecce, quam bonum! (BCP, p. 787). Canticle 16, “The Song of Zechariah,” is often known by its incipit, Benedictus Dominus Deus (BCP, p. 92), and Canticle 21, “You are God,” is often known by its incipit, Te Deum laudamus (BCP, p. 95).
Glossary definitions provided courtesy of Church Publishing Incorporated, New York, NY,(All Rights reserved) from “An Episcopal Dictionary of the Church, A User Friendly Reference for Episcopalians,” Don S. Armentrout and Robert Boak Slocum, editors.