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trisomy 21

noun tri·so·my 21 \ˈtrī-ˌsō-mē-ˌtwen-tē-ˈwən\

Definition of TRISOMY 21

:  Down syndrome
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Origin of TRISOMY 21

from the occurrence of trisomy in chromosome 21 of persons with Down syndrome
First Known Use: 1961
Medical Dictionary

trisomy 21

noun \-ˌtwent-ē-ˈwən\

Medical Definition of TRISOMY 21

:  down syndrome

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