Trisomy
/ˈtraɪ.sə.mi/noun
A condition in which a cell or organism has three copies of a particular chromosome instead of the usual two.
Did you know?The term was coined in modern genetics from Greek roots meaning “three” and “body,” because early cytogenetics described chromosomes as bodies visible under the microscope.
Etymological Timeline
Proto-Indo-European
PIE
*trei-
“three”
Ancient Greek
Greek
treîs (τρεῖς)
“three”
Ancient Greek
Greek
sôma (σῶμα)
“body”
Late 19th–20th Century
Medical/Scientific Latinized Greek
trisomy
“a state of having three chromosomes of a given type”
Modern English
English
trisomy
“the presence of an extra chromosome in a cell or organism”
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