`virtual` marks the gap between what something officially is and what it actually does. Picture a country where one general gives every order and nobody refuse: on paper he holds no title, but in practice he runs the place — he is the `virtual ruler`. The word always points at the effect and quietly admits the fact is missing. Once you hold that, `virtual reality` stops being a separate word: it is a place that does everything a place does, except exist.
From the word’s history
From Medieval Latin virtualis, from Latin virtus "excellence, potency, efficacy". In late 14c. English it meant "effective with respect to inherent natural qualities", and by early 15c. "capable of producing a certain effect" — the word was about what something can DO. From that, the mid-15c. sense "being something in essence or effect, not in fact" follows directly. Optics borrowed it for apparent images (a reflection) by 1831, and computing borrowed it in 1959, first for memory.
virtual 來自中世紀拉丁語 virtualis，源頭是拉丁語 virtus「效能、力量」。14 世紀晚期進入英文時，意思是「就其本身性質而言是有效的」，到 15 世紀初變成「能夠產生某種效果的」——換句話說，這個字一開始講的就是「它做得到什麼」。從這裡直接長出 15 世紀中期的「實質上是、事實上不是」。1831 年光學借走它來指鏡子裡那種看得見卻摸不到的像，1959 年電腦領域再借走一次，最早用在記憶體上（virtual memory）。所以「效果在、實體不在」這條線，從拉丁文一路拉到今天的 VR。
Online Etymology Dictionary, entry "virtual" (etymonline.com/word/virtual)
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原始詞典資料18 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。
virtualadj/ˈvɜːt͡ʃʊəl/
- 1
In effect or essence, rather than in fact or reality; also, imitated, simulated.
- In fact a defeat on the battlefield, Tet was a virtual victory for the North, owing to its effect on public opinion.
- Virtual addressing allows computer applications to believe that there is much more physical memory than actually exists.
- 2
For practical purposes, though not technically; almost complete, very near.
- The angry peasants were a virtual army as they attacked the castle.
- But it vvas plain, that the general reaſonings vvhich vvere employed againſt that povver, vvent directly to our vvhole legiſlative right; and one part of it could not be yielded to ſuch arguments, vvithout a virtual ſurrender of all the reſt.
- 3
computingengineeringmathematicsOperating using a computer and/or online rather than physically present.
- a virtual assistant a virtual personal trainer
- In recent months, hospitals around the country, looking for ways to free up beds for coronavirus patients, began expanding their virtual offerings, launching video doctors' visits and virtual therapy sessions, and rolling out programs to remotely monitor vulnerable patients, like those in nursing homes.
- 4
computingengineeringmathematicsSimulated in a computer and/or online.
- virtual machine virtual memory virtual private network
- The virtual world of his computer game allowed character interaction.
- 5
computingengineeringmathematicsOf a class member: capable of being overridden with a different implementation in a subclass.
- 6
engineeringmechanical-engineeringmechanicsPertaining to a theoretical infinitesimal velocity in a mechanical system that does not violate the system's constraints; also, of other physical quantities: resulting from such a velocity.
- virtual displacement virtual work
- 7
natural-sciencesphysical-sciencesphysicsPertaining to a theoretical quality of something which would produce an observable effect if counteracting factors such as friction are disregarded; specifically, of a head of water: producing a certain pressure if friction, etc., is disregarded.
- 8
engineeringnatural-sciencesopticsChiefly in virtual focus: of a focus or point: from which light or other radiation apparently emanates; also, of an image: produced by light that appears to diverge from a point beyond the reflecting or refracting surface.
另外 7 個記錄的用法
- 9
natural-sciencesphysical-sciencesphysicsPertaining to particles in temporary existence due to the Heisenberg uncertainty principle.
- 10
natural-sciencesphysical-sciencesphysicsOf a quantum state: having an intermediate, short-lived, and unobservable nature.
- 11
obsoleteHaving efficacy or power due to some natural qualities.
- [H]is ſenſes flame / Flovv'd from his parts, vvith force ſo virtuall, / It fir'd vvith ſence things meere inſenſuall.
- Take an Apple, &c. and pricke it vvith a Pin full of Holes, not deepe, and ſmeare it a little vvith Sacke, or Cinnamon vvater, or Spirit of vvine, euery day for ten dayes, to ſee if the Virtuall Heat of the VVine, or Strong VVaters, vvill not Mature it.
- 12
obsoleteHaving efficacy or power due to some natural qualities.
- 13
obsoleteHaving the power of acting without the agency of some material or measurable thing; possessing invisible efficacy.
- VVater, being contiguous vvith Aire, Cooleth it, but Moiſteneth it not, except it Vapour. The Cauſe is, for that Heat, and Cold haue a Virtuall Tranſition, vvithout Communication of Subſtance; but Moiſture not: […]
- 14
obsoleteProducing, or able to produce, some result; effective, efficacious.
- For Dr. [John] Dee, in his Mathematical Preface to Euclids Elements of Geometrie, hath vvorthily taken pains to make Architecture a Mathematical Science; and as a vertual Proof of his ovvn Learned Plea, quotes tvvo Authentique Authors, viz. Vitruvius and Leo Baptiſta [i.e., Leon Battista Alberti], […]
- 15
obsoleteSynonym of virtuous (“full of virtue; having excellent moral character”).
- The moſt in ſoule deiected; the moſt baſe, / And moſt vnſeruiceable weede, vnles / You by your heauenly Influence change his vilenes / Into a vertuall habit fit for vſe.
- Her the grim conqueror's iron might / Avengeing clutched, distrusting rent; / […] / Not virtual France, the France benevolent, / The chivalrous, the many-stringed, sublime / At intervals, and oft in sweetest chime; […]
virtualnoun/ˈvɜːt͡ʃʊəl/
- 1
Preceded by the: that which is imitated or simulated rather than existing in fact or reality; (countable) an instance of this.
- 2
Preceded by the: that which is imitated or simulated rather than existing in fact or reality; (countable) an instance of this.
- 3
computingengineeringmathematicsA virtual (adjective sense 3.3) member function of a class.
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。