Coffer

A coffer (or coffering) in architecture is a series of sunken panels in the shape of a square, rectangle, or octagon in a ceiling, soffit or vault.^[1] A series of these sunken panels was often used as decoration for a ceiling or a vault, also called caissons ("boxes"), or lacunaria ("spaces, openings"),^[2] so that a coffered ceiling can be called a lacunar ceiling: the strength of the structure is in the framework of the coffers.

^ Ching, Francis D.K. (1995). A Visual Dictionary of Architecture. New York: John Wiley & Sons, Inc. p. 30. ISBN 0-471-28451-3.
^ An alternative, in a description of Domitian's audience hall by Statius, noted by Ulrich 2007:156, is laquearia, not a copyist's error, as it appears in Manilius' Astronomica (1.533, quoted by Ulrich).

[ching-1] Ching, Francis D.K. (1995). A Visual Dictionary of Architecture. New York: John Wiley & Sons, Inc. p. 30. ISBN 0-471-28451-3.

[2] An alternative, in a description of Domitian's audience hall by Statius, noted by Ulrich 2007:156, is laquearia, not a copyist's error, as it appears in Manilius' Astronomica (1.533, quoted by Ulrich).

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