symmetrical

American Heritage® Dictionary of the English Language, Fourth Edition

1. adj. Of or exhibiting symmetry.

Century Dictionary and Cyclopedia

1. Well-proportioned in its parts; having its parts in due proportion as to dimensions; harmonious: as, a symmetrical building; his form was very symmetrical.
2. Composed of two parts whose geometrical relations to one another are those of a body and its image in a plane mirror, every element of form having a corresponding element upon the opposite side of a median or symmetral plane, upon one continued perpendicular to that plane and at the same distance from it: said also of each part relatively to the corresponding part: as, the right arm is symmetrical with the left.
3. In a weakened sense, in zoology, having similar parts in reversed repetition on the two sides of a median plane, or meson, through an axis of the body, generally the longitudinal. Not all the parts need so correspond, nor need those which do correspond be equal.
4. Composed of parts or determined by elements similarly related to one another, and either having no determinate order (as the three lines which by their junction form a summit of a cube) or else in regular cyclical order: said also of the parts in their mutual relation.
5. Specifically, in botany, of flowers, numerically regular; having the number of members the same in all the cycles or series of organs—that is, of sepals, petals, stamens, and carpels: same as isomerous, except that in a symmetrical flower there may be more than one set of the same kind of organs. Compare regular, a., 7.
6. In organic chemistry, noting compounds which contain atoms or groups at equal relative intervals in the molecule: thus, for example, chlorobenzene, which has the formula and ethylene chlorid, ClCH₂.CH₂C1, are both symmetrical compounds.

Wiktionary

1. adj. Exhibiting symmetry; having harmonious or proportionate arrangement of parts; having corresponding parts or relations

GNU Webster's 1913

1. adj. Involving or exhibiting symmetry; proportional in parts; having its parts in due proportion as to dimensions.
2. adj. (Biol.) Having the organs or parts of one side corresponding with those of the other; having the parts in two or more series of organs the same in number; exhibiting a symmetry. See Symmetry, 2.
3. adj. Having an equal number of parts in the successive circles of floral organs; -- said of flowers.
4. adj. Having a likeness in the form and size of floral organs of the same kind; regular.
5. adj. (Math.) Having a common measure; commensurable.
6. adj. Having corresponding parts or relations.

WordNet 3.0

1. adj. exhibiting equivalence or correspondence among constituents of an entity or between different entities
2. adj. having similarity in size, shape, and relative position of corresponding parts