Complex sentence: Sometimes the words "anisotropic", "isotropic" and "totally isotropic" are used for nondegenerate, degenerate and totally degenerate respectively, although definitions of these latter words can vary slightly between authors.
Split into simpler sentences: Sometimes the words anisotropic, isotropic and totally isotropic are used for nondegenerate, degenerate and totally degenerate respectively. Although definitions of these latter words can vary slightly between authors.