Down syndrome
noun /ˈdaʊn sɪndrəʊm/
/ˈdaʊn sɪndrəʊm/
(North American English) (also Down's syndrome especially in British English)
[uncountable]- a medical condition, caused by a fault with one chromosome, in which a person is born with particular physical characteristics and a mental ability that is below average
唐氏综合征