an imaginary line through a crystal about which the crystal may be rotated a specified number of degrees and be brought back to its original position.
noun, Crystallography. 1. any of four points, lines, or planes of a crystal: a center of symmetry, a reflection plane, a rotation axis, or a rotation-inversion axis.
noun, Crystallography. 1. reflection plane.
noun 1. John Addington [ad-ing-tuh n] /ˈæd ɪŋ tən/ (Show IPA), 1840–93, English poet, essayist, and critic. noun 1. John Addington (ˈædɪŋtən). 1840–93, English writer, noted for his Renaissance in Italy (1875–86) and for studies of homosexuality
sympath- pref. Variant of sympatho-.