anisotropic, a. [Gr. unequal + a turning, to turn.].
Not isotropic; having different properties in different directions; thus, crystals of the isometric system are optically isotropic, but all other crystals are anisotropic. [1913 Webster]
anisotropic, adj. having physical properties that are different in different directions, e.g. the strength of wood along the grain differing from that across the grain (opp. ISOTROPIC).