Real Dictionary

Tay-Sachs disease in British English
a hereditary condition, found chiefly among descendants of some Eastern European Jews, caused by an enzyme deficiency and characterized by mental retardation, paralysis, and death in early childhood
a rare fatal hereditary disease, occurring chiefly in infants and children, esp. of eastern European Jewish origin, characterized by a red spot on the retina, gradual blindness, and paralysis
noun: an inherited disorder, caused by a faulty recessive gene, in which lipids accumulate in the brain, leading to learning difficulties and blindness. It occurs mostly in Ashkenazi Jews