tau 希臘字母 τ（陶），常見於數學與科學符號。｜字脈

1希臘字母 τ（陶），常見於數學與科學符號。
Tau is the 19th letter of the Greek alphabet, written as τ (lowercase) or Τ (uppercase, which looks like the English letter T). Outside of Greek, English speakers mostly meet this word in math, science, and , where τ is used as a symbol for different things depending on the field — for example, a short amount of time in physics, or a type of statistical measurement.

From Middle English tau, from Latin tau, from Ancient Greek ταῦ and Hebrew tav.

源自希臘字母名 ταῦ 和希伯來文 tav，經拉丁文進入英文。

組成The Greek alphabet, including tau, developed from the earlier Phoenician alphabet.

原始詞典資料14 筆記錄

以下是外部詞典記錄的用法，摘錄並精簡格式，我們還沒有寫成教學內容。上面的說明才是我們自己寫的；有些用法可能上面已經講過了。

Tauname

taunoun/taʊ/

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
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.
3
ChristianityA Τ-shaped object or sign; a Saint Anthony's cross, sometimes regarded as a sacred symbol.
4
The ankh symbol (☥).
5
astronomynatural-sciencesChiefly written τ: used to designate the nineteenth star (usually according to brightness) in a constellation.
6
businessfinanceA 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)
7
mathematicssciencesChiefly 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).

這個拼法也被記錄為下列字的變化形：

摘錄自英文維基詞典 English Wiktionary，已精簡格式；依 CC BY-SA 4.0 授權使用，改動後的內容同樣以此授權提供。