- 1扭轉、扭力作用（工程上指物體受扭轉時內部產生的應力）。torsion bar 是汽車懸吊的扭力桿。日常說「扭」就用 twist 就好。
*Torsion* is twisting — specifically, what happens inside a solid thing when one end is turned one way and the other end is held still or turned the other way. Take a metal bar, grip both ends, and twist: the bar is now under torsion. Engineers use the word for that stress, and they can measure it: a drive shaft in a car, a bridge deck in a strong side wind, and the wing of an all have to be built to survive torsion.
The *torsion bar* is the piece of everyday machinery students are most likely to meet. It is a straight steel bar used as a spring in a car's suspension: instead of coiling like a normal spring, it takes the bump by twisting along its length and then untwisting. Tanks and many older cars used them.
It is a technical word, and I would keep it that way. In ordinary conversation English says *twist* or *twisting*. Nobody complains that the wire has torsion in it; they say it got twisted.
Two other places it turns up, worth knowing because they surprise people. In medicine, *testicular torsion* and *ovarian torsion* are serious emergencies where an organ twists on its own blood supply and cuts off the blood — this is a real, common use in hospitals. And in mathematics, torsion has a precise meaning in geometry and in group theory that has drifted a long way from twisting metal; if a student meets it in a maths book, they should not expect this everyday sense to help them.
The dictionary sometimes lists a verb *to torsion*, but I would tell students : it is very rare and sounds wrong to most ears. Use *twist*.
組成From Latin tortiō, from the verb torqueō, "to twist, turn", reaching English through Middle French torsion and Middle English torcion. The -ion ending makes a noun out of an action, so the whole word is simply "the act or result of twisting".
同家族的字
- torqueTurning force — from the same Latin torqueō. Torque is the force applied; torsion is the twisting it causes in the material.
- tortureSame root: the old idea of the body being twisted and racked.
- distortTo twist something out of its proper shape — the -tort piece is the same root.
- contortionA twisting of the body into an unnatural shape — same root, same -ion ending.
原始詞典資料7 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。
torsionnoun/ˈtɔː.ʃən/
- 1
The act of turning or twisting, or the state of being twisted; the twisting or wrenching of a body by the exertion of a lateral force tending to turn one end or part of it about a longitudinal axis, while the other is held fast or turned in the opposite direction.
- 2
mathematicssciencesA finite order element of a group that, when raised to a positive integer power results in the identity element of the group.
- 3
mathematicssciencesAn element of a homology or cohomology group for which there exists a non-zero integer that, when the element is multiplied by that integer, yields zero.
- 4
medicinesciencesA type of holistic complimentary medicine that involves balancing theoretical energy fields through energy healing, meditation, and similar practices.
- 5
engineeringmechanical-engineeringmechanicsThat force with which a thread, wire, or rod of any material returns, or tends to return, to a state of rest after it has been twisted; torsibility.
- 6
medicinesciencessurgeryThe stopping of arterial haemorrhage in certain cases, by twisting the cut end of the artery.
torsionverb/ˈtɔː.ʃən/
- 1
To subject to torsion.
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。