What does "tau" mean?
The letter Τ /τ in the Greek alphabet; being the nineteenth letter of the Classical and Modern Greek, and the twenty-first letter of the Old and Ancient Greek alphabets.
Tau
/taʊ/ name, noun
name, noun ·Uncommon ·College level
Meaning at a glance
- Primary sense: The letter Τ /τ in the Greek alphabet; being the nineteenth letter of the Classical and Modern Greek, and the twenty-first letter of the Old and Ancient Greek alphabets.
- Grammar: tau is listed as name, noun.
- Nearest alternatives: ankh, chi, crisscross, cross.
- Useful contrasts: instantaneous response, normal stress.
- Usage evidence: In a study reported in the journal Science Translational Medicine, researchers describe how a synthetic drug, called antisense oligonucleotide, reduced the production and in some cases cleared clumps of tau in the brain.
How to use "tau"
- Start with the primary definition, then check the part of speech before placing the word in a sentence.
- Compare nearby synonyms to make sure "tau" carries the exact meaning, tone, and strength you need.
- Use the example sentence as a context check. If your sentence uses the word differently, confirm that the grammar still fits.
Meaning check
- Does the word fit the sentence's grammar?
- Does it match the intended tone rather than only the dictionary definition?
- Would a simpler synonym be clearer for the reader?
- Is there enough surrounding context to prevent ambiguity?
Source and review context
This entry combines structured lexical data with WordToolSet review checks. Definitions, examples, synonyms, and usage notes may come from different source tables, so the page is designed to show evidence from more than one angle before you rely on "tau" in a final draft.
If a word has several senses, prefer the sense that matches your sentence's grammar and surrounding context. A correct definition can still be the wrong choice when the sentence needs a different register, emphasis, or level of specificity.
Before you rely on this definition
Read the first definition as a starting point, then check the example, synonyms, and part of speech before treating "tau" as the right word for your sentence.
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Compare nearby meanings
- Use synonyms when you need a softer, stronger, simpler, or more specific word.
- Use antonyms to check the boundary of the meaning and avoid accidental contrast.
- Use the example sentence to confirm the word behaves naturally in context.
- Keep the original wording when a replacement adds complexity without improving precision.
Definition decision workflow
1. Identify the role
Check whether "tau" is acting as name, noun in your sentence. A definition is only useful when the grammar matches the way the word is being used.
2. Test the nearest option
Compare it with "ankh" and other nearby choices to see whether the sentence needs a softer, stronger, or more familiar word.
3. Confirm with context
Use the example sentence below as an evidence check, then read your own sentence out loud to catch tone or rhythm problems.
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Final meaning check
Before publishing a sentence with "tau", ask whether the word helps the reader understand the idea faster. A precise word should reduce confusion, not simply make the sentence look more polished.
When the definition, synonym evidence, and example context point in the same direction, the word is usually a safer choice. When they conflict, revise the sentence or choose a clearer alternative.
Definitions
Noun
- 1 The letter Τ /τ in the Greek alphabet; being the nineteenth letter of the Classical and Modern Greek, and the twenty-first letter of the Old and Ancient Greek alphabets.
- 2 Abbreviation of treatment as usual. abbreviation, alt-of, countable, uncountable
- 3 the 19th letter of the Greek alphabet wordnet
- 4 Alternative form of taw; the 22nd and last letter of many Semitic alphabets/abjads, including Phoenician, Aramaic, Hebrew, Syriac, and Arabic. alt-of, alternative
"Hence it appears that the spits, or skewers, on which and to which the lamb was fixed and fastened in order to be roasted, assumed the form of a cross, not such a tau-cross as is engraved in Dr. Oliver’s Historical Landmarks of Freemasonry, vol. i. p. 80. having three arms only like the Greek letter tau; but a cross like the ancient Hebrew tau, with four arms, though not necessarily all of equal length."
- 5 A Τ-shaped object or sign; a Saint Anthony's cross, sometimes regarded as a sacred symbol.
"Nor ſhall we take in the myſticall Tau, or the Croſſe of our bleſſed Saviour, which having in ſome deſcriptions an Empedon or croſſing foot-ſtay, made not one ſingle tranſverſion."
Show 8 more definitions
- 6 A Τ-shaped object or sign; a Saint Anthony's cross, sometimes regarded as a sacred symbol.; A crosier with a Τ-shaped head.
- 7 The ankh symbol (☥).
- 8 Chiefly written τ: used to designate the nineteenth star (usually according to brightness) in a constellation.
- 9 A measurement of the sensitivity of the value of an option to changes in the implied volatility of the price of the underlying asset.
"(includes a list of coordinate terms)"
- 10 Chiefly written τ: an irrational and transcendental constant representing the ratio of the circumference of a Euclidean circle to its radius, equal to twice the value of pi (2π; approximately 6.2831853071). neologism
- 11 Ellipsis of tau protein (“a protein abundant especially in the neurons of the human central nervous system that stabilizes microtubules, and when misfolded is associated with forms of dementia such as Alzheimer's and Parkinson's diseases”). abbreviation, alt-of, ellipsis
"Quite what that job is remains obscure, but one theory is that it is to stabilise another protein called tau, which is supposed in turn to keep in shape the tubular ‘skeleton’ of a neuron."
- 12 Chiefly written τ.; Ellipsis of tau lepton or tau particle (“an unstable elementary particle which is a type of lepton, having a mass almost twice that of a proton, a negative charge, and a spin of ½; it decays into hadrons (usually pions) or other leptons, and neutrinos; a tauon”). abbreviation, alt-of, ellipsis, particle
- 13 Chiefly written τ.; Ellipsis of tau meson, now known as a kaon. abbreviation, alt-of, ellipsis, historical, particle
Proper Noun
- 1 A surname from Chinese.
- 2 Initialism of Transvaal Agricultural Union. abbreviation, alt-of, initialism
Antonyms
instantaneous responsenormal stress
Example
"In a study reported in the journal Science Translational Medicine, researchers describe how a synthetic drug, called antisense oligonucleotide, reduced the production and in some cases cleared clumps of tau in the brain."
Common questions
What is a synonym for "tau"?
Common synonyms include: ankh, chi, crisscross, cross, crossbones, crucifix.
How do you use "tau" in a sentence?
In a study reported in the journal Science Translational Medicine, researchers describe how a synthetic drug, called antisense oligonucleotide, reduced the production and in some cases cleared clumps of tau in the brain.
How do you pronounce "tau"?
Pronounced /taʊ/.
Etymology
Etymology 1
From Middle English tau, taue, from Latin tau, from Ancient Greek ταῦ (taû) and Hebrew תָּו (tav). Sense 6 (“mathematical constant equal to 2π”) was used by Joseph M. Lindenberg in 1991, and popularized by the American educator and entrepreneur Michael Hartl in a 2010 paper which explains that τ resembles π; and that τ is the Greek equivalent of t, the first letter of turn, and 2π corresponds to one turn of a circle with a radius of one unit. Sense 8.1 (“ellipsis of tau lepton or tau particle”) was coined by the American physicist Martin Lewis Perl (1927–2014) after the first letter of Ancient Greek τρίτον (tríton, “third”), since the tau lepton or tauon was the third charged lepton discovered.
Etymology 2
Variant of Tao.