-chroic

Also ‑chroism.

Having colour of a given type.

Greek khrēs, colour.

A crystal that is pleochroic (Greek pleon, more) shows different colours when viewed in polarized light at various angles, depending on the underlying structure of the crystal; specifically, a dichroic (Greek di‑, twice) crystal has two such directions, a trichroic one has three. Synthetic dichroic material in flat sheets is used in some kinds of sunglasses. Forms in ‑chroism are nouns for the property concerned: dichroism.