Clerestory. A high range of windows to south and north, above the arcades of a church, enabling the roof to be filled with light, and the rood illuminated.

Characteristic of the late-medieval perpendicular period in architecture, they are most memorable in East Anglia's greatest churches, including Salle and Cawston. Spectacular from the outside, they successfully accomplish Perpendicular architecture's intention to lift the eye to heaven.

It is possible for a clerestory to be on only one side of the building, or to only sit above where the rood was.