| the offspring of a zebra and a donkey. |
| a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison. |
| Down's syndrome or (US) Down syndrome | |
| —n | |
| a. pathol Former name: mongolism, Technical name: trisomy 21 a condition caused by the presence of an extra copy of chromosome 21 resulting in learning difficulties and physical differences, such as shorter stature | |
| b. (as modifier): a Down's syndrome baby | |
| usage | |
| Down syndrome or (US) Down syndrome | |
| —n | |
| usage | |
| Down's syndrome or (US) Down syndrome | |
| —n | |
| a. pathol Former name: mongolism, Technical name: trisomy 21 a condition caused by the presence of an extra copy of chromosome 21 resulting in learning difficulties and physical differences, such as shorter stature | |
| b. (as modifier): a Down's syndrome baby | |
| usage | |
| Down syndrome or (US) Down syndrome | |
| —n | |
| usage | |
Down syndrome (doun) or Down's syndrome (dounz)
n.
A congenital disorder, caused by the presence of an extra 21st chromosome, in which the affected person has mild to moderate mental retardation, short stature, and a flattened facial profile. Also called trisomy 21, trisomy 21 syndrome.
| Down syndrome (doun) or Down's Syndrome (doun) Pronunciation Key
A congenital disorder caused by the presence of an extra 21st chromosome. People with Down syndrome have mild to moderate mental retardation, short stature, and a flattened facial profile. The syndrome is named after its discoverer, British physician John Langdon Haydon Down (1828-1896). |
A congenital condition, caused by an abnormality in the chromosomes, marked by moderate to severe mental retardation and changes in certain physical features.