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Tay-Sachs disease

(tāsăks′)

A hereditary disease that affects young children almost exclusively of eastern European Jewish descent, in which an enzyme deficiency leads to the accumulation of gangliosides in the brain and nerve tissue, resulting in intellectual disability, convulsions, blindness, and, ultimately, death.

[After Warren Tay (1843-1927), British physician, and Bernard Sachs (1858-1944), American neurologist.]

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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