Down syndrome

noun

medical : a condition that someone is born with and that causes below average mental abilities and problems in physical development.

Full Definition of DOWN SYNDROME

: a congenital condition characterized by moderate to severe mental retardation, slanting eyes, a broad short skull, broad hands with short fingers, and trisomy of the human chromosome numbered 21 —called also Down's syndrome

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Origin of DOWN SYNDROME

J. L. H. Down †1896 English physician

First Known Use: 1961

Rhymes with DOWN SYNDROME

aerodrome, astrodome, catacomb, chromosome, close to home, currycomb, double-dome, foster home, funeral home, gastronome, harvest home, hecatomb, hippodrome, honeycomb, loxodrome, meadowfoam, metronome, mobile home, monochrome, motor home, nursing home, onion dome, palindrome, plastic foam, pleasure dome, polychrome, ribosome, semidome, soldiers' home, stay-at-home, Styrofoam, velodrome

Medical Dictionary

Down syndrome

noun

Medical Definition of DOWN SYNDROME

: a congenital condition characterized by moderate to severe mental retardation, upward slanting eyes usually with epicanthic folds, a broad short skull, broad hands with short fingers, decreased muscle tone, and by trisomy of the human chromosome numbered 21—called also trisomy 21

Biographical Note for DOWN SYNDROME

Down \ˈdau̇n\ , John Langdon Haydon (1828–1896), British physician. Down published in 1866 a treatise on the degeneration of race as a result of marriages of consanguinity. He classified individuals exhibiting mental retardation according to the supposed physiognomic features of various races including the American Indian, Caucasian, Ethiopian, and Mongolian. His classification was invalid, but one kind of moderate to severe mental retardation came to be known as mongolism, although it is now called Down syndrome or Down's syndrome.