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Down syndrome

American  
Or Down's syndrome

noun

Pathology.
  1. a genetic disorder, associated with the presence of an extra chromosome 21, characterized by mild to severe mental impairment, weak muscle tone, shorter stature, and a flattened facial profile.


Sensitive Note

Down syndrome (or Down's syndrome ) has replaced earlier terms, such as mongolism to refer to the disease and Mongoloid or Mongol to refer to the affected person, all of which are now considered offensive.

Etymology

Origin of Down syndrome

First recorded in 1960–65; after John L. H. Down (1828–96), British physician