or Down's syndrome
- a genetic disorder, associated with the presence of an extra chromosome 21, characterized by mild to severe mental impairment, weak muscle tone, shorter stature, and a flattened facial profile.
See also trisomy.
Origin of Down syndrome
1960–65; after John L. H. Down (1828–96), British physician
Also called trisomy 21.
Down syndrome (or Down's syndrome ) has replaced earlier terms, such as mongolism to refer to the disease and Mongoloid or Mongol to refer to the affected person, all of which are now considered offensive.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
US Down syndrome
- pathola condition caused by the presence of an extra copy of chromosome 21 resulting in learning difficulties and physical differences, such as shorter statureFormer name: offensive mongolism Technical name: trisomy 21
- (as modifier)a Down's syndrome baby
C19: after John Langdon-Down (1828–96), English physician
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.
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for down's syndrome
1961, from J.L.H. Down (1828-1896), English physician; chosen as a less racist name for the condition than earlier mongolism.
Online Etymology Dictionary, © 2010 Douglas Harper
- 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.trisomy 21 trisomy 21 syndrome
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
- 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).
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.