anisotropy

n. state of having different sizes or characteristics along different axes (Botany and Physics)

Anisotropy (pronounced with stress on the third syllable, ) is the property of being directionally dependent, as opposed to isotropy, which means homogeneity in all directions. It can be defined as a difference in a physical property (absorbance, refractive index, density, etc.) for some material when measured along different axes. An example is the light coming through a polarising lens.
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Anisotropy /an·isot·ro·py/ the quality of being anisotropic. anisotropy, n the condition of not having properties or characteristics that are the [more]Anisotropy - Community and Resources

Noun
1. the property of being anisotropic; having a different value when measured in different directions
(antonym) isotropy, symmetry
(hypernym) property

In hydrology, the conditions under which one or more hydraulic properties of an aquifer vary from a reference point.