The portion of a Gradual containing the ordinary chants (Kyrie, Gloria, Credo, Sanctus, and Agnus dei) of the Mass, that is, the chants whose texts remain unchanged throughout the ecclesiastical year. In the late Middle Ages, the Kyriale sometimes formed a separate volume.

Michelle Brown

Michelle Brown, Understanding Illuminated Manuscripts (Malibu, CA: J. Paul Getty Museum in association with the British Library, c1994).