tau

American  

[tou, 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; tav

Example Sentences

For many years, Alzheimer's disease has been closely associated with amyloid plaques and tau tangles that accumulate in the brain.

From Science Daily • Mar. 12, 2026

Together, these findings suggest that analyzing protein structure in blood could complement existing amyloid and tau tests.

From Science Daily • Mar. 12, 2026

In a study published March 5 in the Cell Press journal Cell Press Blue, researchers describe a newly identified biological process that may help explain how tau builds up.

From Science Daily • Mar. 8, 2026

Neutrinos exist in three varieties, or "flavors," known as electron, muon, and tau.

From Science Daily • Mar. 3, 2026

However, if T. tau and T. upsilon are subspecies, intergrades would be expected between the ranges of the two populations and not on the northeastern and southwestern periphery of their combined ranges.

From The Amphibians and Reptiles of Michoacán, México by Duellman, William E.