tau
Definition, pronunciation, etymology, and usage for the English word. Free spelling reference powered by Wiktionary.
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English
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Detailed reference entry for the English word "tau", 3-letters, with pronunciation in International Phonetic Alphabet notation, etymology traced through Germanic and Romance roots where applicable, common misspelling variants catalogued from Hunspell error dictionaries, and usage frequency ranked against the top 100,000 English words in the Wordfreq corpus. PlainSpell covers English, Spanish, Portuguese, French, and German spelling with confusable-pair detection that highlights visually and phonetically similar words. This entry for "tau" includes synonyms, antonyms, homophones, and cross-language translation pointers sourced from Wiktionary via the kaikki.org extract. Whether you are verifying the correct spelling of "tau" for academic writing, checking homophone confusion, or exploring etymological origins, this page provides a citation-backed, free reference that requires no sign-up.
tau is aEnglishnoun. It means: 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. Pronounced /taʊ/. Often confused with to and TV.
| Property | Value |
|---|---|
| Headword | tau |
| Language | English |
| Part of speech | Noun |
| IPA | /taʊ/ |
| Letters | 3 |
| Frequency rank | #19,983 |
| Misspellings tracked | 0 |
| Confusable pairs | 20 |
| Source | Wiktionary (kaikki.org) |
Frequency rank visualization
Spelling & Dictionary Insight
The English entry for tau is 3 letters long, classified as anoun, and transcribed in the International Phonetic Alphabet as /taʊ/. Corpus data places it at rank #19,983 in overall English word frequency, marking it as uncommon enough that many writers pause before typing it.Wiktionary records 11 distinct senses for this headword, so context determines which meaning a reader should apply.
No frequent misspelling variants are recorded for tau in our index, suggesting the orthography either follows predictable English patterns or the word is uncommon enough that typo corpora lack signal.It also participates in 20 confusable-pair relationships, "to", "TV", "te", and more, where similar look or sound leads writers to substitute one word for another in context.
Etymologically, the entry records: From Middle English tau, taue, from Latin tau, from Ancient Greek ταῦ (taû) and Hebrew תָּו (tav). Sense 7 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 … Root origin matters for spelling because borrowed morphemes (Greek, Latin, Old French, Old English) carry their source-language orthographic conventions into modern English, which is why historical etymology is often the cleanest predictor of whether a cluster like "-ough", "-eau", or "-tion" will appear. For readers arriving here from a spelling check, the authoritative guidance is: the correct English form is tau, spelled T-A-U, and any other sequence of those letters, regardless of how natural it feels, is a misspelling in standard orthography.
Definition
- 1The 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.
- 2Alternative form of taw; the 22nd and last letter of many Semitic alphabets/abjads, including Phoenician, Aramaic, Hebrew, Syriac, and Arabic.
- 3A Τ-shaped object or sign; a Saint Anthony's cross, sometimes regarded as a sacred symbol.
- 4A Τ-shaped object or sign; a Saint Anthony's cross, sometimes regarded as a sacred symbol.
- 5The ankh symbol (☥).
- 6Chiefly written τ: used to designate the nineteenth star (usually according to brightness) in a constellation.
- 7A measurement of the sensitivity of the value of an option to changes in the implied volatility of the price of the underlying asset.
- 8Chiefly 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).
- 9Ellipsis 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”).
- 10Chiefly written τ.
- 11Chiefly written τ.
Etymology
From Middle English tau, taue, from Latin tau, from Ancient Greek ταῦ (taû) and Hebrew תָּו (tav). Sense 7 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.
This word in other languages
Frequency rank: #19,983 in English
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Nearby English words
Other entries that begin with the letter T in our English index: