Down syndrome

noun
variants: or Down's syndrome

Definition of Down 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

First Known Use of Down syndrome

1961, in the meaning defined above

History and Etymology for Down syndrome

J. L. H. Down †1896 English physician

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The first known use of Down syndrome was in 1961

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Cite this Entry

“Down syndrome.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Down%20syndrome. Accessed 28 Jul. 2021.

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More Definitions for Down syndrome

Down syndrome

noun

English Language Learners Definition of Down syndrome

medical : a condition that someone is born with and that causes below average mental abilities and problems in physical development

Down syndrome

noun
variants: or Down's syndrome

Medical Definition of Down 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

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