bars or ribs, usually of stone or wood, or other material, that subdivide an opening or stand in relief against a door or wall as an ornamental feature
In architecture, bars or ribs used decoratively in windows, especially the ornamental openwork in Gothic windows. In the earliest phase, two or three narrow, arched windows were placed close together under a single large arch, with the section of wall between the small and large arches pierced by a circular or four-lobed opening. The complexity of this plate tracery increased, reaching a climax in the magnificent windows of Chartres Cathedral. After 1220 windows began to be subdivided by mullions, or upright bars, that continued at the head of the window to branch and form the patterns of bar tracery. Elaborate bar tracery soon became one of the most important elements of Gothic architecture and one of its finest achievements, as in the rose windows of the French Rayonnant style. The bar tracery of the parallel English Decorated style formed netlike patterns based on the circle, arch, trefoil, and quatrefoil. By the late 14th century, the Perpendicular style replaced curvilinear tracery with straight mullions extending to the top of the main arch, connected at intervals by horizontal bars
Gothic window ornamentation depending on window mullions in elaborate flowing or geometrical patterns built up of curved lengths of mortared stone molding
intersecting ribwork in the upper part of a window, or used decoratively in blank arches, on vaults, etc
Delicate latticelike forms of bars and lines, whose spaces either contain glass or are left open Derived from Gothic windows in which a framework within any large window was necessary to hold the glass (which at that time was manufactured in small sections) Tracery should properly contain separate pieces of glass, but most modern work uses a cutout pattern of filigree over a single pane of glass
the geometrical architectural ornamentation which is used in Gothic architecture to subdivide the upper parts of the arches belonging to large windows, and later to subdivide gable ends, walls, and other surfaces