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

His father Brian said it was an "extremely worrying and traumatic" time and he believed if Joel, who has Down's syndrome, had been vaccinated he would not have needed hospital treatment.

From BBC • Jan. 13, 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

Ms Pickard, 41, who also works for Mencap Cymru, said having Down's syndrome was like a hurdles race.

From BBC • Sep. 9, 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

The 32-year-old, who has a daughter with Down's syndrome and a son awaiting neuro and cognitive assessments, said the campsite "facilitates everybody".

From BBC • Aug. 28, 2025