One of the two possible orientations of an angle, i.e. clockwise or anticlockwise. A map is sense-preserving if it maintains the sense of angles. So, a rotation is sense-preserving and a reflection is sense-reversing. A square matrix A represents a sense-preserving linear map if detA> 0 and a sense-reversing map if detA<0. See also positively oriented, right-handed system.