In architecture, an arris is the sharp edge formed by the intersection of two surfaces, such as the corner of a masonry unit; the edge of a timber in timber framing; the junction between two planes of plaster or any intersection of divergent architectural details. Also the raised edges which separate the flutings in a Doric column. The origin of the term arris is from the Latin 'arista' meaning the beard of an ear of grain or the bone of a fish. See also arête.