It is often vaulted and lit by openings in the vault. In the letters of Pliny the Younger, the term is used as a synonym of crypt. The shade and semi-excavated site of a cryptoportico provided cool and moderated temperatures useful for storage of perishables, while it offered a level and slightly raised podium for the superstructure.

The cryptoporticus of Arles, dating from the 1st century BC was built as foundation for the forum, which has since been replaced by the Chapel of the Jesuit College and the City Hall. Three double, parallel tunnels arranged in the form of a U are supported by fifty piers. Masons’ marks on the stonework indicate that it was built by Greeks, probably from Marseille. Similar structures in Narbonne, Reims, and Bavay were used as granaries. The cryptoporticus at Arles is, however, too damp for prolonged storage and may have served as a barracks for public slaves.

The cryptoporticus of Reims, formerly enclosing three sides of the forum, is of Gallo-Roman origin and was probably built during the 3rd century. Today, only its Eastern part remains, but this is unusually well preserved for a Gallo-Roman structure.

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When used on the facade of a chaitya hall, it is called a chaitya arch. It is sometimes called a gavaksha (or kudu, in Tamil) when used as a decorative element on a structural temple.

Examples include Ellora Caves 9, Ajanta Caves 9 and 19 and Varaha Cave Temple at Mamallapuram.

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The emperor Carinus gave great dissatisfaction by promoting one of his Cancellarii to be Praefectus urbi. The cancellarius also signified a legal scribe or secretary, who sat within the cancelli or lattice-work, by which the crowd was kept off from the tribunals of the judges.

The chief scribe or secretary was called Cancellarius, and was eventually invested with judicial power at Constantinople, but an account of his duties and the history of this office do not fall within the scope of the present work. From this word has come the modern Chancellor.

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Cantilevers are widely found in construction, notably in cantilever bridges and balconies (see corbel). In cantilever bridges the cantilevers are usually built as pairs, with each cantilever used to support one end of a central section. The Forth Bridge in Scotland is a famous example of a cantilever truss bridge.

Temporary cantilevers are often used in construction. The partially constructed structure creates a cantilever, but the completed structure does not act as a cantilever. This is very helpful when temporary supports, or falsework, cannot be used to support the structure while it is being built (e.g., over a busy roadway or river, or in a deep valley).

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Casement windows were the most common house window before the sash window was introduced, and usually contain leaded glass. These casement windows usually were hinged on the side, and opened inward. The windows were covered by functional exterior shutters, which opened outward.

They are opened with a crank or a lever or cam handle placed at around hand height or at the bottom and serve as window locks. A crank, stay, or friction hinge is necessary when the window opens outward, to hold the window in position despite wind.

Often the glass panes are set in a rabbeted frame and sealed with beveled putty or glazing compound to secure the glass.

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In Ancient Greek and Roman temples the cella is a room at the centre of the building, usually containing a cult image or statue (execrated by Early Christians as an "idol") representing the particular deity venerated in the temple. In addition the cella may contain a table or plinth to receive votive offerings such as votive statues, precious and semi-precious stones, helmets, spear and arrow heads, and swords. The accumulated offerings made Greek and Roman temples virtual treasuries, and many of them were indeed used as treasuries during antiquity.

The cella is typically a simple, windowless, rectangular room with a door or open entrance at the front behind a colonnaded portico facade. In larger temples, the cella was typically divided by two colonnades into a central nave flanked by two aisles. A cella may also contain an adyton, an inner area restricted to access by the priests—in religions that had a consecrated priesthood—or by the temple guard.

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Structures such as elevators, escalators, and staircases are often referred to as circulation elements, as they are positioned and designed to optimize the flow of people through a building.

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Experimentation with the possible shapes of coffering, which solve problems of mathematical tiling, or tessellation, were a feature of Islamic as well as Renaissance architecture. The more complicated problems of diminishing the scale of the individual coffers were presented by the requirements of curved surfaces of vaults and domes.

A prominent example of Roman coffering, employed to lighten the weight of the dome, can be found in the ceiling of the rotunda dome in the Pantheon, Rome.

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Conch, or the whole apse  after the scallop shell often carved as decoration of the semi-dome (all shells were conches in Ancient Greek), though this is usually used for subsidiary semi-domes, rather than the one over the main apse. Small semi-domes have been often decorated in a shell shape from ancient times, as in Piero della Francesca’s Throned Madonna with saints and Federigo da Montefeltro, and the example in the gallery below.

Islamic examples may use muqarnas decorative corbelling, while in Late Antique, Byzantine and medieval church architecture the semi-dome is the classic location for a focal mosaic, or later fresco.

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In Romanesque work copings appeared plain and flat, and projected over the wall with a throating to form a drip. In later work a steep slope was given to the weathering (mainly on the outer side), and began at the top with an astragal; in the Decorated style there were two or three sets off; and in the later Perpendicular Period these assumed a wavy section, and the coping mouldings continued round the sides, as well as at top and bottom, mitreing at the angles, as in many of the colleges at Oxford.

A coping may consist of stone, brick, tile, slate, metal, wood or thatch. In all cases it should be weathered to throw off the water.

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