Geison

Geison (Ancient Greek: γεῖσον – often interchangeable with somewhat broader term cornice) is an architectural term of relevance particularly to ancient Greek and Roman buildings, as well as archaeological publications of the same. The geison is the part of the entablature that projects outward from the top of the frieze in the Doric order and from the top of the frieze course (or sometimes architrave) of the Ionic and Corinthian orders; it forms the outer edge of the roof on the sides of a structure with a sloped roof. The upper edge of the exterior often had a drip edge formed as a hawksbeak molding to shed water; there were also typically elaborate moldings or other decorative elements, sometimes painted. Above the geison ran the sima. The underside of the geison may be referred to as a soffit. The form of a geison (particularly the Hawksbeak molding of the outer edge) is often used as one element of the argument for the chronology of its building.

Horizontal geison

The horizontal geison runs around the full perimeter of a Greek temple, projecting from the top of the entablature to protect it from the elements and as a decorative feature. Horizontal geisa may be found in other ancient structures that are built according to one of the architectural orders. The horizontal sima (with its antefixes and water-spouts) ran above the horizontal geison along the sides of a building, acting as a rain gutter and final decoration.