Tracery is a series of intersecting ribs used in Gothic architecture, especially windows and, in the Perpendicular Gothic style, vaulting.
Tracery is the stonework used to support the glass in a stained glass window. When used in windows, it is usually supported by carved vertical shafts. However, it is also used in circular rose windows, where there are no supporting shafts, unless they form a separate window underneath. Unusually, though, Lichfield Cathedral's nave clerestory has rose windows which take the form of triangles with curved sides.
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