What architectural feature is referred to as a "flying buttress"?

A flying buttress is an architectural feature primarily used in Gothic architecture that serves a critical structural purpose. It is a support structure designed to transfer the load of a roof or vault away from the walls of a building, effectively allowing for higher ceilings and larger windows. By channeling the weight outward and downward to a separate support, the flying buttress helps maintain the stability of the overall structure while enabling the design of thinner walls.

This structural innovation is particularly significant in churches and cathedrals where large stained glass windows are often incorporated. The design maximizes light and aesthetic appeal without compromising the integrity of the building. In contrast, the other options pertain to different aspects of architecture or masonry that do not capture the essence of how a flying buttress functions within a structure. For instance, a decorative wall element is more about aesthetics rather than structural support, while a technique for laying bricks and a tool used in bricklaying are related to the construction process rather than a feature of the building itself.