1. A congenital disorder caused by having an extra 21st chromosome; results in a flat face, short stature and mental retardation
   "Early intervention helps children with trisomy 21 reach their full potential";
   - mongolism [archaic], Down's syndrome, Down syndrome

Type of: birth defect, congenital abnormality, congenital anomaly, congenital defect, congenital disease, congenital disorder, trisomy

Encyclopedia: Trisomy 21