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

The Centers for Disease Control and Prevention (CDC) says Down syndrome can affect how a person's brain and body develop, but that doesn't mean those with it can't live a healthy and happy life. —Lucy Notarantonio, MSNBC Newsweek, 15 Aug. 2025

Among those arrested is a minor with Down syndrome who has been separated from his family and was sent to the state of New York on Thursday morning, said the attorney, Nikolas De Bremaeker. —Shomik Mukherjee, Mercury News, 14 Aug. 2025

The expansion more than doubles the space dedicated to pediatric rehab and offer support for autism, cerebral palsy, spinal cord injuries, traumatic brain injuries, scoliosis, Down syndrome, torticollis, dysphagia and multi-traumas after motor vehicle accidents, according to the release. —Lillian Metzmeier, The Courier-Journal, 11 Aug. 2025

One 2025 study indicated that facial recognition tools had higher error rates for adults with Down syndrome. —Janice Gassam Asare, Forbes.com, 6 Aug. 2025

Word History

Etymology

J. L. H. Down †1896 English physician

First Known Use

1961, in the meaning defined above

Rhymes for Down syndrome

• acrosome
• aerodrome
• catacomb
• centrosome
• chromosome
• cytochrome
• hippodrome
• honeycomb
• liposome
• meerschaum
• metronome
• microtome

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