\ ˈtau̇ How to pronounce tau (audio) , ˈtȯ\

Definition of tau

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

Recent Examples on the Web

The National Institute on Aging has supported a $47 million add-on to include tau and amyloid imaging (toxic brain proteins linked with Alzheimer’s). San Diego Union-Tribune, "Progress in understanding Alzheimer’s disease genetics, hope remains for drugs in testing," 2 Sep. 2019 Her brain was shriveled and filled with clumps of proteins—which scientists later identified as amyloid beta and tau. Katherine Ellen Foley, Quartz, "There are a lot of promising blood tests for Alzheimer’s—here’s how to keep track," 1 Aug. 2019 Further testing pointed increasingly to the likelihood of C.T.E., which is characterized by elevated amounts of a protein, tau, that slowly kills brain cells. Richard Sandomir, New York Times, "Nick Buoniconti, 78, Dies; All-Pro Linebacker Championed Medical Research," 31 July 2019 Their 2009 paper presented evidence of tau’s role in reducing neurological and cognitive function in football players and other athletes who suffer repetitive brain trauma. SI.com, "A History of Football in 100 Objects," 28 Aug. 2019 There are three types of neutrinos, referred to as the three flavors: electron, muon, and tau neutrinos. David Grossman, Popular Mechanics, "Ghost Particles Could Explain Just About Everything in the Universe," 23 Aug. 2019 Not only that, the scientists also found that damage to brain regions involved in daytime wakefulness was caused by a protein called tau. chicagotribune.com, "Too much napping may signal Alzheimer’s," 22 Aug. 2019 There are three kinds—the electron neutrino, the muon neutrino, and the tau neutrino. Nandita Jayaraj, Quartz India, "Meet Indumathi, the Indian scientist who wants to capture one of the universe’s smallest particles," 27 Aug. 2019 For example, the neutrinos made at Fermilab, nearly all of which will be of a flavor called muon, could arrive in South Dakota as muon neutrinos, or either of the two other flavors, tau or electron neutrinos. Nathaniel Scharping, Discover Magazine, "Why Fermilab is Making A Neutrino Detector 800 Miles Long," 12 Mar. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'tau.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of tau

14th century, in the meaning defined at sense 1

History and Etymology for tau

Middle English taw, from Latin tau, from Greek, of Semitic origin; akin to Hebrew tāw taw

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14 Oct 2019

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The first known use of tau was in the 14th century

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\ ˈtau̇ How to pronounce tau (audio) , ˈtȯ How to pronounce tau (audio) \

Medical Definition of tau

: 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

called also tau protein

More from Merriam-Webster on tau

Rhyming Dictionary: Words that rhyme with tau

Britannica.com: Encyclopedia article about tau

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