noun. A partial loss of pigmentation in a human or other animal, resulting in white, pale, or patchy coloration of the skin, hair, fur, or feathers but not the eyes.

noun. In zoology, whiteness resulting from lack or loss of coloring; albinism, partial or complete: a technical term, correlated with melanism and erythrism. See albinism.

noun. An animal condition characterized by reduced pigmentation.

"Initially it was thought the deer was suffering from albinism, but experts now believe a rare genetic mutation resulting in a condition called leucism has changed the deer's pigmentation."

albinism