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In architecture and masonry, the term set-off is given to the horizontal line shown on a floorplan indicating a reduced wall thickness, and consequently the part of the thicker portion appears projecting before the thinner. In plinths, this is generally simply chamfered. In other parts of stonework, the set-off is generally concealed by a projecting stringer. Where, as in parapets, the upper part projects (is "proud of") the lower, the break is generally hid by a corbel watertable. The portions of buttress caps which recede one behind another are also called sets-off.