Tympanum
In architecture, a tympanum (plural, tympana; from Latin and Greek words meaning "drum") is the semi-circular or triangular decorative wall surface over an entrance, door or window, which is bounded by a lintel and an arch. It often contains sculpture or other imagery or ornaments.
Most architectural styles include this element.
For a good example in my work, see Krishna Slaying the Demon Kamsa, Banteay Srei, Angkor, Cambodia. 2019.
See also Angkor Architectural Styles.
Also in Angkorpedia
