orthorhombic

adj. pertaining to the rhombic crystallization pattern, pertaining to the crystallization pattern characterized by three unequal axes that intersect at right angles (Mineralogy)

In crystallography, the orthorhombic crystal system is one of the 7 lattice point groups. Orthorhombic lattices result from stretching a cubic lattice along two of its lattice vectors by two different factors, resulting in a rectangular prism with a rectangular base (a by b, which is different from a) and height (c, which is different from a and b). All three bases intersect at 90° angles. The three lattice vectors remain mutually orthogonal.
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(a.)
Noting the system of crystallization which has three unequal axes at right angles to each other; trimetric. See Crystallization.