- 1（數學）切線；片語 go off on a tangent 表示「離題」
In geometry, a tangent is a straight line that touches a curve at just one point, without crossing into it. In everyday speech, though, 'go off on a tangent' is the phrase you'll hear most — it means to suddenly start talking about something that isn't really connected to the main topic.
From the word’s history
From Latin tangentem, from tangēns 'touching', from tangō 'touch'.
借自拉丁文 tangēns「接觸的」，來自 tangō「碰觸」：切線。
組成From Latin tangere, 'to touch.'
原始詞典資料8 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。
tangentnoun/ˈtæn.d͡ʒənt/
- 1
A straight line touching a curve at a single point without crossing it there.
- One feature of the body, which is constructed of pressed-steel members, is the contour of the sides. They are in the form of a continuous radius from the bottom side to the cant rail, and to enable flat glass windows to be fitted the side panels are pressed around the window opening, forming a tangent to the curved bodyside.
- 2
mathematicssciencesA function of an angle that gives the ratio of the sine to the cosine, in either the real or complex numbers. Symbols: tan, tg.
- 3
A topic nearly unrelated to the main topic, but having a point in common with it.
- I believe we went off onto a tangent when we started talking about monkeys on unicycles at his retirement party.
- “Uncle Barnaby was always father and mother to me,” Benson broke in; then after a pause his mind flew off at a tangent. “Is old Hannah all right—in the will, I mean?”
- 4
artartsA visual interaction between two or more lines or edges that creates a perceived relationship between them, often in a way that the artist did not intend.
- 5
entertainmentlifestylemusicA small metal blade in a clavichord that strikes the strings to produce sound.
tangentadj/ˈtæn.d͡ʒənt/
- 1
geometrymathematicssciencesTouching a curve at a single point but not crossing it at that point.
- 2
Of a topic, only loosely related to a main topic.
- 3
rail-transportrailwaystransportStraight; not horizontally curved.
- The collision occurred on a two-mile stretch of tangent track.
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。