trisomy-21

1 definition found

trisomy-21 - Collaborative International Dictionary of English v.0.48 :

  Down syndrome \Down" syn`drome\, Down's syndrome \Down's"
  syn`drome\, n. (Med.)
     A congenital disorder caused by an extra chromosome 21 in
     some or all cells. It causes a variable number and degree of
     abnormalities, including retarded growth, mental retardation,
     a short nose, prominent epicanthic folds on the eyelids, a
     protruding lower lip, and other physical features having
     varying degrees of deviation from the normal. Called also
     mongolism, trisomy-21 and trisomy 21 syndrome.
     [PJC]