Ex-trā'dos, n.
n. [Fr., from Lat. extra, and Fr. dos, equivalent to Lat. dorsum, the back.] (Arch.) The exterior curve of an arch;—usually the upper curve of voussoirs or stones forming the arch. Gwilt.
n. [Fr., from Lat. extra, and Fr. dos, equivalent to Lat. dorsum, the back.] (Arch.) The exterior curve of an arch;—usually the upper curve of voussoirs or stones forming the arch. Gwilt.