from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Variant of Down syndrome.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Condition caused by a chromosomal deficiency, whereby the patients bear a certain resemblance to the Mongoloid race, such as a small head and tilted eyelids.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a congenital disorder caused by having an extra 21st chromosome; results in a flat face and short stature and mental retardation
Named after John L.H. Langdon-Down (1828-1896), an English physician who described it in the late 1800s. The term was first used in 1961. (Wiktionary)