triforium, in architecture, space in a church above the nave arcade, below the clerestory, and extending over the vaults, or ceilings, of the side aisles. The term is sometimes applied to any second-floor gallery opening onto a higher nave by means of arcades or colonnades, like the galleries in many ancient Roman basilicas or Byzantine churches. The triforium became an integral part of church design during the Romanesque period, serving to light and ventilate the roof space. With the development of the Gothic vaulting system in France, the triforium diminished in size and importance. The cathedrals at Reims (begun 1211) and Amiens (1220–47) both have triforia of little relative height but with rich arcading.
or
clerestory, in architecture, any fenestrated (windowed) wall of a room that is carried higher than the surrounding roofs to light the interior space. In a large building, where interior walls are far from the structure’s exterior walls, this method of lighting otherwise enclosed, windowless spaces became a necessity. One of the earliest uses of the clerestory was in the huge hypostyle hall of King Seti I and Ramses II at the Temple of Amon (1349–1197 bc, Karnak, Egypt), in which the central range of columns, higher than those on either side, permitted clerestories to be built of pierced stone slabs.
Both are architectural terms, I'm not an architect but read up on Gothic architecture while I was studying the Use of Sarum. A more enjoyable six weeks I have never spent.
Topic: How about a favorite words thread? (Read 11397 times)