Down syndrome definition by Wordo

Noun

A

genetic disorder

caused

by

the

presence

of

all

or

part

of

a

third

copy

of

chromosome

21

(

a

chromosomal

excess

),

whereby

the

patients

typically

have

a

delay

in

cognitive

ability

and

physical

growth

,

as

well

as

a

small

head

and

tilted

eyelids

.