癩病[raibyou] Hansen's disease
癩病患者[raibyoukanja] leper
癩菌[raikin] Mycobacterium leprae
救癩[kyuurai] helping the lepers

白癩[shirahatake] vitiligo
白癩[byakurai] white leprosy
黒癩[kokurai] black leprosy

お歯黒[ohaguro] tooth blackening
暗黒期[ankokuki] eclipse period
暗黒時代[ankokujidai] Dark Ages
暗黒大陸[ankokutairiku] Dark Continent (i.e. Africa)
黒い[kuroi] black

黒い霧[kuroikiri] thick fog
黒くする[kurokusuru] to blacken
黒ずむ[kurozumu] to blacken
黒っぽい[kuroppoi] dark