1
: the 19th letter of the Greek alphabet see Alphabet Table
2
: a short-lived elementary particle of the lepton family that exists in positive and negative charge states and has a mass about 3500 times greater than an electron
called also tau particle
3
: a protein that binds to and regulates the assembly and stability of neuronal microtubules and that is found in an abnormal form as the major component of neurofibrillary tangles
Examples of tau in a Sentence
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Both former heavy drinkers and heavy drinkers also had higher odds of developing tau tangles, an Alzheimer’s biomarker.5
Why Does Drinking Make the Brain More Prone to Injury?
—
Cathy Nelson, Health, 7 May 2025
The scientists looked for signs of brain injury, including tau tangles (abnormal accumulations of protein linked to Alzheimer’s disease) and hyaline arteriolosclerosis (a condition that causes small blood vessels to narrow and become thick and stiff).
—Tom Gavin, EverydayHealth.com, 10 Apr. 2025
Heavy drinkers also had a higher likelihood of developing tau tangles.
—Katia Hetter, CNN Money, 9 Apr. 2025
By then, the company that administers the tests had added a measurement for tau, another key hallmark sign of Alzheimer’s, frontal lobe dementia and Lewy body disease.
—Sandee Lamotte, CNN, 18 June 2024
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Cathy Nelson, Health, 7 May 2025
The scientists looked for signs of brain injury, including tau tangles (abnormal accumulations of protein linked to Alzheimer’s disease) and hyaline arteriolosclerosis (a condition that causes small blood vessels to narrow and become thick and stiff).
—Tom Gavin, EverydayHealth.com, 10 Apr. 2025
Heavy drinkers also had a higher likelihood of developing tau tangles.
—Katia Hetter, CNN Money, 9 Apr. 2025
By then, the company that administers the tests had added a measurement for tau, another key hallmark sign of Alzheimer’s, frontal lobe dementia and Lewy body disease.
—Sandee Lamotte, CNN, 18 June 2024
See All Example Sentences for tau
Cite this Entry
“Tau.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tau. Accessed 4 Aug. 2025.
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tau
noun
ˈtau̇ 
ˈtȯ
: the 19th letter of the Greek alphabet
—Τ or τ
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