Down syndrome

• Down’s syndrome (chiefly in the UK and Canada)

Named after John Langdon Haydon Down (1828–1896), an English physician who first described the condition as a distinct form of mental disability in the 1860s.

• (Received Pronunciation) IPA^(key): /daʊn ˈsɪndɹəʊm/
• (General American) IPA^(key): /daʊn ˈsɪndɹoʊm/, /-dɹəm/

• Audio (General Australian):

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• Hyphenation: Down syn‧drome

Down syndrome (uncountable)

1. (neurology, chiefly US, Australia, New Zealand) A genetic disorder caused by the presence of all or part of a third copy of chromosome 21 (a chromosomal excess), whereby the patients typically have a delay in cognitive ability and physical growth, as well as a small head and tilted eyelids. [from 1961.]

The condition is known only as Down's syndrome in the UK and Canada.

• Down's (informal)
• mongolism, Mongolian idiocy (now offensive)
• trisomy 21

• Down syndrome regression disorder

•   Down syndrome on Wikipedia.Wikipedia