An architectural trefoil -- the double outline of the area of three overlapping circles. This appears in Gothic architecture, and is a minor Christian Trinitarian symbol. Can also appear with one lobe on top (the vertical reflection of what is shown).

In the version of the trefoil shown, the circles are pulled as far apart as they can be without creating a gap in the center (i.e. the radius of the three innermost circular white areas is the distance of the separation between the centers of each pair of circles divided by the square root of three). This is more or less the "canonical" form of the trefoil.

See also Image:Trefoil-Architectural-Equilateral-Triangle-outlined.png , Image:Trefoil-Architectural-Equilateral-Triangle-interlaced.png , and Image:Quatrefoil-Architectural.png .

For a sketch of a trefoil actually used in architecture, see Image:Rose.cathedrale.Sees.png .

This is an SVG version of Image:Trefoil-Architectural.png .

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