A term that describes a shape that remains unchanged when it is turned less than 360 degrees about a fixed point
The rotational symmetry of any figure is determined by counting the number of times it semblance repeats or reproduces itself in one rotation about an axis. Only four kinds of rotational symmetry are possible among regular figure; these are twofold, threefold, fourfold, and sixfold. For example a cube has twofold, threefold and fourfold rotational symmetry.
A figure has -fold rotational symmetry if the figure can be rotated degrees about a point (where is a positive integer) in such a way that the resulting image coincides with the original figure (Lesson 0.1).
A figure has rotational symmetry when it can be rotated around a central point, or point of rotation less than 360° and still be identical to the original figure.
Rotational symmetry is symmetry with respect to some or all rotations in m-dimensional Euclidean space. Rotations are direct isometries, i.e., isometries preserving orientation. Therefore a symmetry group of rotational symmetry is a subgroup of E+(m) (see Euclidean group).