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.

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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

Example Sentences

"There's lots of really talented people with Down syndrome out there who are making things, but it kind of reinforces the narrative that people with Down syndrome can't and it must be AI," he said.

From Barron's • Jun. 18, 2026

YouTuber Jesse Ridgway and his wife, Ashley, shared that they terminated their pregnancy following a Down syndrome diagnosis.

From Los Angeles Times • Jun. 5, 2026

We heard from a mother, Opal Foster, whose 18-year-old son has Down syndrome and lives at home as he strives to become a chef.

From Salon • Apr. 29, 2026

Alistair also takes an interest in the intellectual and developmental disabilities community, writing about the effects of the Covid-19 pandemic and war in Ukraine on people with autism, Down syndrome and other conditions.

From The Wall Street Journal • Feb. 16, 2026

He was probably about three or four years old and looked exactly like Ximena, except for the fact that it was very obvious he had Down syndrome.

From "Auggie & Me" by R. J. Palacio