An ogee (pronounced /oʊˈdʒiː/ or /ˈoʊdʒiː/) is a curve (often used in molding), shaped somewhat like an S, consisting of two arcs that curve in opposite senses, so that the ends are parallel.
The term has uses in architecture, mathematics, and fluid mechanics, as well as marine construction, clock design and plastic surgery.
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In architecture, the term is used for a molding with an ogee-shaped profile, consisting (going from low to high) of a concave arc flowing into a convex arc, with vertical ends; if the lower curve is convex and higher one concave, this is known as a Roman ogee, although frequently the terms are used as if they are interchangeable and for a variety of other shapes. Alternative names for such a true Roman ogee molding include cyma reversa and talon.
The cyma reversa form occurs in antiquity. For example, in ancient Persia, the Tomb of Cyrus featured the cyma reversa.[1] The cyma reversa is also evident in ancient Greek architecture.[2] The ogee shape is one of the characteristics of the Gothic style of architecture, especially decorative elements in the 14th and 15th century late Gothic styles called Flamboyant in France and Decorated in England. Ogee windows and arches were introduced to European cities from the Middle East. The ogee curve is an analogue of a "cyma curve", the difference being that a cyma has horizontal rather than vertical ends.
The ogee and Roman ogee profiles are used in decorative molding, often framed between moldings with a square section. As such it is part of the standard classical decorative vocabulary, adopted from architrave and cornice moldings of the Ionic order and Corinthian order. An ogee is also often used in the "crown molding" frequently found at the top of a piece of case furniture, or for capping a baseboard or plinth, or where a wall meets the ceiling. An ogee molding may be run in plaster or wood, or cut in stone or brickwork.
Ogee is also a mathematical term, meaning an inflection point; the aesthetic appeal of the ogee curve forms part of the leitmotif of the Booker-prize winning novel The Line of Beauty.
In fluid mechanics, the term is used for an ogee-shaped aerodynamic profile. For example, a wing may have ogee profile, particularly on supersonic aircraft such as the Concorde. Also, the downstream face of a dam spillway is usually formed in an ogee curve to minimize water pressure.
An "ogee washer" is a heavy washer with a large bearing surface used in marine timber construction to prevent bolt heads or nuts from sinking into the face of timbers. The term ogee is used due to the ogee shape in radial symmetry around the center. Due to the size and shape, they are generally manufactured as a cast iron product in accordance with ASTM A47 or A48.
An "ogee clock" is a common kind of weight-driven 19th-century pendulum clock in a simplified Gothic taste, made in the United States for a mantelpiece or to sit upon a wall bracket. It is rectangular, with ogee-profile molding that frames a central glass door that protects the clock face and the pendulum. The door usually carries a painted scene in the area beneath the face. Ogee clocks are one of the most commonly encountered varieties of American antique clocks.
In aesthetic facial surgery, the term is used to describe the malar or cheekbone prominence transitioning into the mid-cheek hollow. The aim of a mid-face rejuvenation is to restore the ogee curve and enhance the cheekbones. This enhancement is also commonly a part of a routine facelift.
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