crystal system

noun

: any of the six or sometimes seven main groups into which crystals are commonly classified according to the relative lengths and inclinations of their axes or according to their respective symmetries see hexagonal system, isometric system, monoclinic system, orthorhombic system, rhombohedral system, tetragonal system, triclinic system, trigonal system

Word History

First Known Use

1847, in the meaning defined above

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