A trefoil () is a graphic form composed of the outline of three overlapping rings, used in

architecture Architecture is the art and technique of designing and building, as distinguished from the skills associated with construction. It is both the process and the product of sketching, conceiving, planning, designing, and constructing building ...

and Christian symbolism, among other areas. The term is also applied to other symbols with a threefold shape. A similar shape with four rings is called a quatrefoil.

Architecture

Ornamentation

'Trefoil' is a term in

Gothic architecture Gothic architecture (or pointed architecture) is an architectural style that was prevalent in Europe from the late 12th to the 16th century, during the High and Late Middle Ages, surviving into the 17th and 18th centuries in some areas. It ...

given to the ornamental foliation or cusping introduced in the heads of window-lights,

tracery Tracery is an architectural device by which windows (or screens, panels, and vaults) are divided into sections of various proportions by stone ''bars'' or ''ribs'' of moulding. Most commonly, it refers to the stonework elements that support the ...

, and panellings, in which the centre takes the form of a three-lobed

leaf A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, ste ...

(formed from three partially overlapping circles). One of the earliest examples is in the plate tracery at

Winchester Cathedral The Cathedral Church of the Holy Trinity,Historic England. "Cathedral Church of the Holy Trinity (1095509)". ''National Heritage List for England''. Retrieved 8 September 2014. Saint Peter, Saint Paul and Saint Swithun, commonly known as Winches ...

(1222–1235). The fourfold version of an architectural trefoil is a quatrefoil. A simple trefoil shape in itself can be symbolic of the

Trinity The Christian doctrine of the Trinity (, from 'threefold') is the central dogma concerning the nature of God in most Christian churches, which defines one God existing in three coequal, coeternal, consubstantial divine persons: God th ...

, while a trefoil combined with an equilateral triangle was also a moderately common symbol of the Christian Trinity during the

late Middle Ages The Late Middle Ages or Late Medieval Period was the period of European history lasting from AD 1300 to 1500. The Late Middle Ages followed the High Middle Ages and preceded the onset of the early modern period (and in much of Europe, the Renai ...

in some parts of Europe, similar to a barbed quatrefoil. Two forms of a trefoil combined with a triangle are shown below: File:Trefoil-Architectural-Equilateral-Triangle-outlined.svg, alt=The outline of three interlocking circles with an equilateral triangle in the centre., Outlined File:Trefoil-Architectural-Equilateral-Triangle-interlaced.svg, alt=Three interlocking circles with a triangle in the centre, the full, interlocking lines of each now shown., Interlaced A

dove Columbidae () is a bird family consisting of doves and pigeons. It is the only family in the order Columbiformes. These are stout-bodied birds with short necks and short slender bills that in some species feature fleshy ceres. They primarily ...

, which symbolizes the Holy Spirit, is sometimes depicted within the outlined form of the trefoil combined with a triangle.

Architectural layout

In architecture and archaeology, a 'trefoil' describes a layout or

floor plan In architecture and building engineering, a floor plan is a technical drawing to scale, showing a view from above, of the relationships between rooms, spaces, traffic patterns, and other physical features at one level of a structure. Dimensio ...

consisting of three

apse In architecture, an apse (plural apses; from Latin 'arch, vault' from Ancient Greek 'arch'; sometimes written apsis, plural apsides) is a semicircular recess covered with a hemispherical vault or semi-dome, also known as an '' exedra''. ...

s in clover-leaf shape, as for example in the

Megalithic temples of Malta The Megalithic Temples of Malta ( mt, It-Tempji Megalitiċi ta' Malta) are several prehistoric temples, some of which are UNESCO World Heritage Sites, built during three distinct periods approximately between 3600 BC and 2500 BC on the island coun ...

. Particularly in church architecture, such a layout may be called a "triconchos". File:Evolution du plan des temples copie.jpg, alt=A diagram of six examples of evolving temple floor plans, evolving clockwise, labelled ("temple typology"). The floor plans evolve from small, simple rooms to much larger and more elaborate constructions., Evolution of layout of Maltese Megalithic temples; Skorba (upper right) has a typical trefoil plan File:Trikonchos.gif, alt=A triconchos floor plan, showing a wall with a door on the left side and three trefoil-like alcoves on the right., A typical triconchos

Heraldry

The

heraldic Heraldry is a discipline relating to the design, display and study of armorial bearings (known as armory), as well as related disciplines, such as vexillology, together with the study of ceremony, rank and pedigree. Armory, the best-known bran ...

'trefoil' is a stylized

clover Clover or trefoil are common names for plants of the genus ''Trifolium'' (from Latin ''tres'' 'three' + ''folium'' 'leaf'), consisting of about 300 species of flowering plants in the legume or pea family Fabaceae originating in Europe. The genus ...

. It should not be confused with the figure named in French heraldry ("threefoil"), which is a stylized flower with three petals, and differs from the heraldic trefoil in being not slipped. File:Héraldique meuble trèfle 1.svg, Trefoil in heraldry File:Blason famille fr Duprat.svg, ''Or a fess sable between three trefoils vert'' File:Blason ville fr Boissy-sans-Avoir (Yvelines).svg, ''Gules a cross flory argent between four tiercefeuilles Or'' File:16. varaždinska.jpg, Croatian trefoil badge worn by

Royal Croatian Home Guard The Royal Croatian Home Guard ( hr, Kraljevsko hrvatsko domobranstvo, Hrvatsko-slavonsko domobranstvo or Kraljevsko hrvatsko-ugarsko domobranstvo, often simply ''Domobranstvo'' or ''Domobran'' in singular, in German: ''Croatisch-Slawonische Landw ...

during

Austria-Hungary Austria-Hungary, often referred to as the Austro-Hungarian Empire,, the Dual Monarchy, or Austria, was a constitutional monarchy and great power in Central Europe between 1867 and 1918. It was formed with the Austro-Hungarian Compromise of ...

, depicting oak leaves File:CroatianTrefoil.svg, Croatian trefoil used by the

Axis An axis (plural ''axes'') is an imaginary line around which an object rotates or is symmetrical. Axis may also refer to: Mathematics * Axis of rotation: see rotation around a fixed axis * Axis (mathematics), a designator for a Cartesian-coordinat ...

-sympathetic

Croatian Air Force Legion The Croatian Air Force Legion ( hr, Hrvatska Zrakoplovna Legija), or HZL, was a unit of the Luftwaffe, composed entirely of volunteers drawn from the nazi puppet-state, the Independent State of Croatia. Many of them had previously served in the Ro ...

in World War II, formed from a defaced ''

Balkenkreuz The ''Balkenkreuz'' () is a straight-armed cross that was first introduced in 1916–1918 and later became the emblem of the ''Wehrmacht'' (German Armed Forces) and its branches from 1935 until the end of World War II. It was used by the '' Wehr ...

Symbols

Symmetrical trefoils are particularly popular as warning and informational symbols. If a box containing hazardous material is moved around and shifted into different positions, it is still easy to recognize the symbol, while the distinctive trefoil design of the

recycling symbol The universal recycling symbol ( or in Unicode) is internationally recognized for symbol for recycling activity. The symbol's creation originates on the first Earth Day in 1970, where the logo depicted is a Möbius strip. The public domain s ...

makes it easy for a consumer to notice and identify the packaging the symbol has been printed on as recyclable. Easily stenciled symbols are also favored. File:Radiation warning symbol.svg, Ionizing radiation hazard trefoil File:Fallout shelter symbol.svg,

Fallout shelter A fallout shelter is an enclosed space specially designated to protect occupants from radioactive debris or fallout resulting from a nuclear explosion. Many such shelters were constructed as civil defense measures during the Cold War. During ...

trefoil File:Biohazard symbol.svg, Biological hazard trefoil File:Recycle001.svg, Universal

File:Pictogram_VORTAC.svg, VORTAC Aircraft Navigation Beacon File:WikiProject Scouting trefoil fade.svg, One particular stylized form of the heraldic trefoil is used as the main element in the logo of most

Girl Guiding and Girl Scouting A Girl Guide or Girl Scout is a member of a section of some Guiding organisations who is between the ages of 10 and 14. Age limits are different in each organisation. The term Girl Scout is used in the United States and several East Asian co ...

organizations. For Girl Scouts, the three trefoil leaves represent the three-fold promise: "To serve God and my country, to help people at all times, and to live by the Girl Scout law." While the green trefoil is considered by many to be the symbol of Ireland, the harp has much greater officially recognized status. Therefore, shamrocks generally do not appear on Irish coins or postage stamps. A trefoil is also part of the logo for

Adidas Originals Adidas Originals (often stylized as adidas Originals) is a brand of a line of casual and sportswear created by German multinational corporation Adidas. It consists of a heritage line, specializing in athletic shoes, t-shirts, jackets, bags, ...

, which also includes three stripes.

Notes

References

External links

{{wiktionary, trefoil
Explanation of Christian symbolism of Trefoil
Ornaments Christian symbols Symbols Heraldic charges Visual motifs Piecewise-circular curves