tau

noun

ˈtau̇ 

ˈtȯ

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

Two sets of similar but heavier particles can pop into brief existence: the muon, muon neutrino, charm quark, and strange quark; and the tau, tau neutrino, top quark, and bottom quark. —Byadrian Cho, science.org, 28 Mar. 2024

When people with high levels of tau — who are thought to be further along in the disease — were included, the benefit compared with placebo was 22%. —Meg Tirrell, CNN, 8 Mar. 2024

Under the proposal, tens of millions of Americans with normal cognition would test positive for abnormal levels of amyloid or tau, the two proteins the tests look for, and the majority of them may never be diagnosed with dementia, studies suggest. —Melody Petersen, Los Angeles Times, 14 Feb. 2024

But what if your brain already has signs of beta amyloid or tau — two of the hallmark signs of Alzheimer’s and other brain pathologies? —Sandee Lamotte, CNN, 5 Feb. 2024

These unique blood tests could determine levels of amyloid, tau and other hallmark biomarkers for Alzheimer’s disease and other degenerative conditions. —Sandee Lamotte, CNN, 12 Feb. 2024

The study involved 164 older people, from ages 68 to 94, who were tested for the presence of the Alzheimer’s proteins amyloid and tau in their brains. —Alice Park, Time, 14 June 2023

The accumulation of too much tau, however, can be a bad thing: Doctors often see a build-up of tau tangles in the brains of Alzheimer’s patients. —Sarah Kuta, Smithsonian Magazine, 8 Nov. 2023

One especially interesting mutation occurred in the MAPT gene, which codes for proteins called tau. —Sarah Kuta, Smithsonian Magazine, 8 Nov. 2023

Word History

Etymology

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

First Known Use

14th century, in the meaning defined at sense 1

Phrases Containing tau

• tau cross

Kids Definition

tau

noun

ˈtau̇ 

ˈtȯ

: the 19th letter of the Greek alphabet

—Τ or τ

Medical Definition

tau

noun

ˈtau̇  ˈtȯ 

: 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