EXEDRA  , or ExHEDRA (from Gr. i , out, and ihpa, a seat), an architectural

term originally applied to a seat or recess out of doors, intended for conversation . Such recesses were generally semicircular, as in the important example built by Herodes Atticus at Olympia . In the great Roman thermae (baths) they were of large size, and like apses were covered with a hemispherical vault . An example of these exists at Pompeii in the Street of the Tombs . From Vitruvius we learn that they were often covered over, and they are described by him (v .