TAU

tau

(noun) the 19th letter of the Greek alphabet

Source: WordNet® 3.1


Etymology

Noun

tau (plural taus)

The letter Τ/τ in the Greek, Hebrew and ancient Semitic alphabets, being the nineteenth letter of the Classical and Modern Greek, the twenty-first letter of Old and Ancient Greek.

A -shaped sign or structure; a Saint Anthony's cross, sometimes regarded as a sacred symbol.

(particle) An unstable heavy lepton, which decays into a muon or electron; a tauon.

(biology) Tau protein, a type of protein that stabilizes microtubules in the human central nervous system, failures of which are associated with forms of dementia.

(finance) A measurement of the sensitivity of the value of an option to changes in the implied volatility of the price of the underlying asset.

(mathematics, neologism) An irrational and transcendental constant representing the ratio of the circumference of a Euclidean circle to its radius, approximately 6.2831853071; equal to twice the value of pi. Often written τ or 2π.

Synonyms

• (measure of derivative price sensitivity): kappa, vega

Hypernyms

• (measure of derivative price sensitivity): Greeks (includes list of coordinate terms)

Coordinate terms

• (Greek letter): Previous: sigma. Next: upsilon

Anagrams

• AUT, UAT, UTA, Uta, aut-

Source: Wiktionary


Tau, n. Etym: [Gr. tay^ the letter t (English T).] (Zoöl.)

Definition: The common American toadfish; -- so called from a marking resembling the Greek letter tau (t). Tau cross. See Illust. 6, of Cross.

Source: Webster’s Unabridged Dictionary 1913 Edition



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