Formwork to support the voussoirs of an arch during construction.

1. A wedge-shaped brick used in arch or circular construction; its two larger faces are inclined toward each other. 2.

A curved brace, usually used in pairs to support a roof frame and give the effect of an arch.

A curved wrought-iron or steel bar used to support the weight of the masonry above a fireplace or window opening.

Any narrow elongated surface forming part of, or connected with, an arch.