crystal system

American  

noun

Crystallography.

1. any of the six main classifications of crystals and of crystal lattices according to their symmetry: isometric, hexagonal, tetragonal, orthorhombic, monoclinic, and triclinic.

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crystal system British  

noun

1. crystallog any of six, or sometimes seven, classifications of crystals depending on their symmetry. The classes are cubic, tetragonal, hexagonal, orthorhombic, monoclinic, and triclinic. Sometimes an additional system, trigonal, is distinguished, although this is usually included in the hexagonal system See also crystal class

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