Definitions for "Birefringent"
() Having two or three refractive indices. Minerals that crystallize in the tetragonal and hexagonal crystal systems have two indices of refraction. Minerals that crystallize in the orthorhombic, monoclinic, and triclinic crystal systems have three indices of refraction.
relating to or characterized by double refraction
Having a refractive index that differs for light of different polarizations. Several crystalline materials such as calcite exhibit birefringence.