A tympanum (plural, tympana) is the semi-circular or triangular decorative wall surface over an entrance bounded by a lintel and arch.[1] It often contains sculptures or other ornaments.[2] Most architectural styles include this element.[3] The tympanum was invented in ancient Egypt in the first half of the 3rd century BC, and later appears in Greek, Christian and Islamic architecture.[4] In Greek and Christian architecture, tympanums usually contained religious scenes.[5]
Bands of molding surrounding the tympanum are referred to as the archivolt.[6]