| 释义 |
symmetry (of a geometrical figure) A figure may have reflective symmetry in a line (axis) or plane or may have rotational symmetry. The term also refers to a transformation of the figure which maps the figure to itself; these symmetries form the symmetry group under composition. As an example, a square is symmetrical about four lines and has rotational symmetry of order 4 about its centre, and so the square has 8 symmetries in all.
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