In geometry, a circular segment or disk segment (symbol: ⌓) is a region of a disk which is "cut off" from the rest of the disk by a straight line. The complete line is known as a secant, and the section inside the disk as a chord.
More formally, a circular segment is a plane region bounded by a circular arc (of less than π radians by convention) and the circular chord connecting its endpoints.
The Ponte Vecchio (Italian pronunciation: [ˈponte ˈvɛkkjo]; "Old Bridge") is a medieval stone closed-spandrel segmental arch bridge over the Arno, in Florence, Italy. The only bridge in Florence spared from destruction during World War II, it is noted for the shops built along it; building shops on such bridges was once a common practice. Butchers, tanners, and farmers initially occupied the shops; the present tenants are jewellers, art dealers, and souvenir sellers. The Ponte Vecchio's two neighbouring bridges are the Ponte Santa Trinita and the Ponte alle Grazie.
The bridge connects Via Por Santa Maria (Lungarno degli Acciaiuoli and Lungarno degli Archibusieri) to Via de' Guicciardini (Borgo San Jacopo and Via de' Bardi).
In architecture, a vault (French voûte, from Italian volta) is a self-supporting arched form, usually of stone or brick, serving to cover a space with a ceiling or roof. As in building an arch, a temporary support is needed while rings of voussoirs are constructed and the rings placed in position. Until the topmost voussoir, the keystone, is positioned, the vault is not self-supporting. Where timber is easily obtained, this temporary support is provided by centering consisting of a framed truss with a semicircular or segmental head, which supports the voussoirs until the ring of the whole arch is completed.
The Mycenaeans (ca. 1800–1050 BC) were known for their tholos tombs, also called beehive tombs, which were underground structures with conical vaults. This type of vault is one of the earliest evidences of curved brick architecture without the use of stone arches, and its construction represented an innovative technique for covering circular spaces.
In 2-dimensional geometry, a lens is a convex region bounded by two circular arcs joined to each other at their endpoints. In order for this shape to be convex, both arcs must bow outwards (convex-convex). This shape can be formed as the intersection of two circular disks. It can also be formed as the union of two circular segments (regions between the chord of a circle and the circle itself), joined along a common chord.