lectorium

a gallery or loft of wood or stone, existing as early as the eleventh century and used, instead of the cancelli, to separate the choir from the nave; it was called the lectorium, or odeum, as the loft where the singers were, and doxale from the singing of the doxologies.

The Catholic Encyclopedia, Volume 12: Philip II-Reuss 1840-1916 1913

Traditional monastic plans usually situated the cloister arcade to the south of the church, allowing the inhabitants to then use the cloister range adjacent to the church as a scriptorium or lectorium which took advantage of the southern sun.

Sensual Encounters: Monastic Women and Spirituality in Medieval Germany 2008