English
leucism
From leuco- + -ism.
Proto-Indo-European *lewk- ‘white’
Proto-Hellenic *leukós ‘white’
Ancient Greek λευκός ‘white’
English leuco
Today it means
noun An animal condition in which there is partial loss of pigmentation resulting in white, pale, or patchy coloration of the skin, hair, feathers, scales or cuticle, but not the eyes (caused by a reduction in multiple types of pigment, not just melanin).
Language periods are conventional ranges, not dates for this word.
Etymograph / leucism