Down syndrome

noun

variants or Down's syndrome

: a congenital condition characterized especially by developmental delays, usually mild to moderate impairment in cognitive functioning, short stature, upward slanting eyes, a flattened nasal bridge, broad hands with short fingers, decreased muscle tone, and by trisomy of the human chromosome numbered 21

called also trisomy 21

Examples of Down syndrome in a Sentence

Recent Examples on the Web

McMorris Rogers, who chairs the House Energy and Commerce Committee, has a son with Down syndrome. —Joanne Haner, The Hill, 4 Dec. 2024

Amani Joy Ward, born with Down syndrome, had dealt with health issues including heart surgery. —Jerry McDonald, The Mercury News, 2 Dec. 2024

People seem less inclined to speculate, for example, about alternative explanations for Down syndrome, which causes intellectual disabilities and has long been known to be caused by an extra copy of chromosome 21. —Liz Szabo, NBC News, 22 Nov. 2024

There are both physical and developmental symptoms of Down syndrome. —Angelica Stabile, Fox News, 7 Oct. 2024

Word History

Etymology

J. L. H. Down †1896 English physician

First Known Use

1961, in the meaning defined above

Kids Definition

Down syndrome

noun

ˈdau̇n-

variants or Down's syndrome

ˈdau̇n(z)-

: a genetic condition characterized especially by developmental delays, by distinctive physical traits (as short stature and upward slanting eyes), and by the presence of three chromosomes numbered 21 in human beings

Etymology

named for J.L.H. Down, 1828–1896, English doctor

Medical Definition

Down syndrome

noun

variants or Down's syndrome

: a congenital condition characterized especially by developmental delays, usually mild to moderate impairment in cognitive functioning, short stature, relatively small head, upward slanting eyes usually with epicanthal folds, flattened nasal bridge, broad hands with short fingers, decreased muscle tone, and by trisomy of the human chromosome numbered 21

called also Down, Down's, trisomy 21