tau

American  

[tau, taw, tahv, tawv] / taʊ, tɔ, tɑv, tɔv /

noun

1. the 19th letter of the Greek alphabet (T,τ ).

2. the consonant sound represented by this letter.

3. tav.

4. Physics. Also tauon tau lepton.

5. Also called tau protein. Biochemistry. a protein that is an important component of nerve cells, helping to maintain their function and structure: in the brain, distortions in the protein’s molecular shape is associated with the onset of Alzheimer’s disease.

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tau British  

/ taʊ, tɔː /

noun

1. the 19th letter in the Greek alphabet (Τ, τ), a consonant, transliterated as t

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Etymology

Origin of tau

1250–1300; Middle English < Latin < Greek taû < Semitic; cf. tav

Example Sentences

See Examples For:

tau

Yet the amount of tau tangles in the brain did not change.

From Science Daily ● Sep. 28, 2026

A signature brain protein in some forms of FTD is tau, the same one that causes damage to different brain regions in Alzheimer’s.

From The Wall Street Journal ● Sep. 25, 2026

Their brains activated the later microglial program, but this response occurred largely without being tied to tau accumulation.

From Science Daily ● Jul. 26, 2026

At a later stage, they moved into a different antigen-presenting state that appeared at the same time as tau pathology.

From Science Daily ● Jul. 26, 2026

The partial cross-shape figure in it is merely the conventional method of drawing the opening between the fingers, and would be just as correctly given as an oval as an inverted tau.

From Day Symbols of the Maya Year Sixteenth Annual Report of the Bureau of American Ethnology to the Secretary of the Smithsonian Institution, 1894-1895, Government Printing Office, Washington, 1897, pages 199-266. by Cyrus Thomas