The individual wedge-shaped arch stones or bricks whose converging sides are cut according to one or more radii depending on the type of arch or vault.
Repetition with variation. This echo in the parts of what manifests in the whole or climax is well exemplified in the minor domes of Santa Maria del Fiore which prepare the viewer for Brunelleschi's great dome that would otherwise overwhelm the composition.
A large semi-circular window typically divided by two mullions or alternatively four mullions into an odd number of compartments. The core of the Thermae commissioned by the Roman Emperor Diocletian is largely preserved, windows included, within the Basilica Santa Maria degli Angeli.
An oriel balcony of Islamic architecture typically projecting over the street that features elaborately carved screens allowing for the passage of light and air while offering privacy.
The design was maintained and incorporated into Western architecture on the Iberian peninsula and subsequently in Latin America such as the early 20th century example of the Archbishop's Palace in Lima, Peru.
The Flamboyant (French for "flaming") later period of predominantly French Gothic architecture characterized by flowing, ogee window traceries resembling flickering flames.
French for "to thread" (as in a needle), architecturally it refers to a suite of rooms directly connected, the doors aligned along a common axis. Frequently employed in palace architecture of the Baroque period, guests would be escorted to the farthest room their rank would permit.
A compound curve combining a concave and convex curve in a continuous line, otherwise referred to as an S-curve. They are often used to form moulding profiles, arches, roofs or a tracery as in this handsome circa 1923 Gothic Revival example I saw recently at All Saints Episcopal Church in Pasadena, CA.
A large, circular window often placed in the gable of a church or cathedral, with tracery laid out in a radial pattern and an interior window of stained glass.
This Norman church in Kent, England features the most amazing of grotesque ornamentation.
Contributed by Patrick Webb