medallion

 A medallion (or medaillon, from the French médaillon) is a round or oval frame (often made of stucco) that contains a sculptural or pictorial decoration on a façade, an interior, a piece of furniture or equipment.

A medallion on a façade in Trento

In the United Kingdom in the 19th century, this was a popular form of decoration in neoclassical architecture. The frame and portrait were carved as one, in marble for interiors, and in stone for exterior walls.

It is also the name of a scene that is inset into a larger stained glass window.

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 Metasyntactic variable, which is released under the 
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