Down's syndrome

British  

noun

1. 1. Former name: mongolism.  Technical name: trisomy 21.  offensive pathol a condition caused by the presence of an extra copy of chromosome 21 resulting in learning difficulties and physical differences, such as shorter stature

   2. ( as modifier )

      a Down's syndrome baby

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Down's syndrome Cultural  

1. A congenital condition, caused by an abnormality in the chromosomes, marked by moderate to severe mental retardation and changes in certain physical features.

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Usage

Although the condition was once generally known as mongolism , this term has been considered offensive since the early 1960s. The terms Down's syndrome or ( US ) Down syndrom are now preferred.

Etymology

Origin of Down's syndrome

C19: after John Langdon-Down (1828–96), English physician

Example Sentences

It comes after the BBC flagged dozens of profiles showing AI-generated images of women with disabilities, including Down's syndrome or vitiligo.

From BBC • Feb. 26, 2026

Ellie has had hundreds of messages over the last few months from families who have relatives with Down's syndrome.

From BBC • Dec. 31, 2025

Dot Gallagher's son Michael, 38, is in a relationship with Alison Williams, 42, and they both have Down's syndrome.

From BBC • Dec. 28, 2025

The presenter, who has Down's syndrome, says: "I'm looking forward to sword fighting, the Tinkerbell stuff - everything really, it's just so exciting."

From BBC • Sep. 9, 2025

Loraine had Down's syndrome and her mother was her carer.

From BBC • Jul. 26, 2025