tau
[ tou, taw for 1, 2, 4; tahv, tawv for 3 ]
/ taʊ, tɔ for 1, 2, 4; tɑv, tɔv for 3 /
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noun
the 19th letter of the Greek alphabet (T, τ).
the consonant sound represented by this letter.
tav.
Also tau·on [tou-on] /ˈtaʊ ɒn/ .Physics. tau lepton.
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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Origin of tau
1250–1300; Middle English <Latin <Greek taû<Semitic; cf. tav
Words nearby tau
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021
How to use tau in a sentence
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British Dictionary definitions for tau
tau
/ (tɔː, taʊ) /
noun
the 19th letter in the Greek alphabet (Τ, τ), a consonant, transliterated as t
Word Origin for tau
C13: via Latin from Greek, of Semitic origin; see tav
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Medical definitions for tau (1 of 2)
τ
The Greek letter tau. Entries beginning with this character are alphabetized under tau.
Medical definitions for tau (2 of 2)
tau
n.
The 19th letter of the Greek alphabet.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.










