noun. Ornamental work consisting of three-dimensional frets; geometric openwork.

noun. Such ornamental work represented two dimensionally by chiaroscuro.

noun. Ornamental work consisting of a series or combination of frets; ornamental work with interlacing parts; especially, work in which the design is formed by perforation.

noun. Work adorned with frets; ornamental openwork or work in relief, esp. when elaborate and minute in its parts. Hence, any minute play of light and shade, dark and light, or the like.

noun. ornamental woodwork either carved in low relief or cut through with a fretsaw

noun. framework consisting of an ornamental design made of strips of wood or metal

"The walls apparently were hewn from black rock, and at regular intervals, placed some three feet from these gleaming walls, uprose slender golden pillars supporting a kind of fretwork arch which entirely masked the ceiling."