virtualとは 意味・読み方・使い方

語源

The adjective is derived from Middle English vertual, virtual [and other forms],^[1] from Old French vertüal, vertüelle (modern French virtuel), or from their etymon Medieval Latin virtuālis (“of または pertaining to potency または power; having power to produce an effect, potent; morally virtuous”), from Latin virtūs (“goodness, virtue; manliness, virility”) (from vir (“adult male, man”) (ultimately from Proto-Indo-European *wiHrós (“man”), possibly from *weyh₁- (“to chase, hunt, pursue”)) + -tūs (suffix forming collective または abstract nouns)) + -ālis (suffix forming adjectives of relationship), modelled after virtuōsus (“good, virtuous”).^[2]

Sense 4 (“pertaining to a theoretical infinitesimal velocity in a mechanical system that does not violate the system’s constraints”) is borrowed from French virtuel,^[2] from Middle French virtuel, from Old French vertüal, vertüelle: see above.

The noun is derived from the adjective.^[2]

発音

• (Received 発音) IPA^(key): /ˈvɜːt͡ʃʊəl/, /ˈvɜːt͡ʃ(ʊ)l/
• (General American) IPA^(key): /ˈvɜɹt͡ʃuəl/
• (New Zealand) IPA^(key): /ˈvɵːt͡ʃuəl/, /ˈvɵːt͡ʃəl/, [ˈvɵːt͡ʃɯ(l)]
• 韻: -ɜː(ɹ)tʃuəl, -ɜːtʃəl
• ハイフネーション: vir‧tu‧al

形容詞

virtual (not comparable)

1. In effect or essence, rather than in fact or reality; also, imitated, simulated.

   Synonym: de facto

   Antonyms: actual, real, true, veritable

   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.

   • 1653 (indicated as 1654), Jeremy Taylor, “The Real Presence and Spiritual of Christ in the Blessed Sacrament, Proved against the Doctrine of Transubstantiation. Section I. State of the Question.”, in Reginald Heber, editor, The Whole Works of the Right Rev. Jeremy Taylor, D.D. […], volume IX, London: Ogle, Duncan, and Co. […] and and Richard Priestley, […], published 1822, →OCLC, paragraph 13, page 432:

     [W]e affirm, that Christ is really taken by faith, by the Spirit, to all real effects of his passion; they say, he is taken by the mouth, and that the spiritual and the virtual taking him, in virtue or effect, is not sufficient, though done also in the sacrament.

   • 1840, Thomas De Quincey, “Style”, in Critical Suggestions on Style and Rhetoric with German Tales and Other Narrative Papers (De Quincey’s Works; XI), London: James Hogg & Sons, published 1859, →OCLC, part I, page 165:

     And the true art for such popular display is to contrive the best forms for appearing to say something new, when in reality you are but echoing yourself; to break up massy chords into running variations; and to mask, by slight differences in the manner, a virtual identity in the substance.

   • 1857, William Fleming, “VIRTUAL”, in The Vocabulary of Philosophy, Mental, Moral, and Metaphysical; […], London, Glasgow: Richard Griffin and Company, →OCLC, page 542:

     VIRTUAL is opposed to actual.— […] A thing has a virtual existence when it has all the conditions necessary to its actual existence. The statue exists virtually in the brass or iron, the oak in the acorn.

2. For practical purposes, though not technically; almost complete, very near.

   The angry peasants were a virtual army as they attacked the castle.

   • 1769, [Edmund Burke], Observations on a Late State of the Nation, London: […] J[ames] Dodsley, […], →OCLC, page 77:

     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.

   • 2012 September 24, “Capital One Cup Third Round: Chelsea 6 – 0 Wolves”, in BBC Sport‎^[1], archived from the original on 2012-11-25:

     The Chelsea captain [John Terry] was a virtual spectator as he was treated to his side's biggest win for almost two years as Stamford Bridge serenaded him with chants of "there's only one England captain," some 48 hours after he announced his retirement from international football.

3. (computing)
   1. Operating using a computer and/or online rather than physically present.

      a virtual assistant    a virtual personal trainer

      • 2020 August 10, Abigail Abrams, “Tech Companies are Transforming People’s Bedrooms into ‘Virtual Hospitals.’ Will It Last Post-COVID?”, in Time‎^[2], New York, N.Y.: Time Warner Publishing, →ISSN, →OCLC, archived from the original on 2023-03-28:

        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.

   2. Simulated in a computer and/or online.

      virtual machine    virtual memory    virtual private network

      The virtual world of his computer game allowed character interaction.

   4. (object-oriented programming) Of a class member: capable of being overridden with a different implementation in a subclass.
5. (mechanics) Pertaining 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

6. (physics)
   1. Pertaining 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.
   2. (optics) Chiefly 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.

      Antonym: real

   3. (particle physics) Pertaining to particles in temporary existence due to the Heisenberg uncertainty principle.
   4. (quantum mechanics) Of a quantum state: having an intermediate, short-lived, and unobservable nature.
7. (obsolete)
   1. Having efficacy or power due to some natural qualities.
      • 1598, George Chapman, “Third Sestyad”, in Christopher Marlo[w]e, George Chapman, Hero and Leander: […], London: […] A[ugustine] M[atthews] for Richard Hawkins: […], published 1629, →OCLC:

        [H]is ſenſes flame / Flovv'd from his parts, vvith force ſo virtuall, / It fir'd vvith ſence things meere inſenſuall.

      • 1631, Francis [Bacon], “IV. Century. [Experiments in Consort Touching Maturation, and the Accelerating thereof. And First Touching the Maturation and Quickening of Drinks. And Next Touching the Maturation of Fruits..]”, in Sylua Syluarum: Or A Naturall Historie. In Ten Centuries. […], 3rd edition, London: […] William Rawley and [p]rinted by J[ohn] H[aviland] for William Lee […], paragraph 326, page 84, →OCLC:

        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.

      • 1667, John Milton, “Book X”, in Paradise Lost. […], London: […] [Samuel Simmons], […], →OCLC; republished as Paradise Lost in Ten Books: […], London: Basil Montagu Pickering […], 1873, →OCLC, lines 336–338:

        [H]is [God's] Omnipreſence fills / Land, Sea, and Aire, and every kinde that lives, / Fomented by his virtual power and warmd: […]

      • 1733, Philip Miller, “RAIN”, in The Gardeners Dictionary: […], 2nd edition, volume I, London: […] C[harles] Rivington, […], →OCLC, column 1:

        RAIN is generally accounted to be a crude Vapour of the Earth, but more eſpecially of the Sea, dravvn up from thence by the attractive Povver of the Sun, or carry'd thithervvard by Pulſion, and vvafted by the VVinds into the Aerial Region; by vvhich Sublimation and Rarefaction, and the virtual Qualities of the Sun and Air, it is form'd into Clouds.

      1. (specifically, also figuratively) Of a plant or other thing: having strong healing powers; virtuous.
   2. Having the power of acting without the agency of some material or measurable thing; possessing invisible efficacy.
      • 1631, Francis [Bacon], “IX. Century. [Experiment Solitary, Touching the Working of Water vpon Aire Contiguous.]”, in Sylua Syluarum: Or A Naturall Historie. In Ten Centuries. […], 3rd edition, London: […] William Rawley and [p]rinted by J[ohn] H[aviland] for William Lee […], paragraph 865, page 223, →OCLC:

        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: […]

   3. Producing, or able to produce, some result; effective, efficacious.
      • 1683, Joseph Moxon, “Numb[er] I. Applied to the Art of Printing. Preface.”, in Mechanick Exercises: Or, The Doctrine of Handy-Works. Applied to the Art of Printing. […], volume II, London: […] Joseph Moxon […], →OCLC, pages 5–6:

        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], […]

   4. Synonym of virtuous (“full of virtue; having excellent moral character”)
      • 1607, Thomas Dekker, “The Whore of Babylon. […]”, in The Dramatic Works of Thomas Dekker […], volume II, London: John Pearson […], published 1873, →OCLC, page 216:

        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.

      • 1898, George Meredith, “Alsace-Lorraine”, in Odes in Contribution to the Song of French History, Westminster, London: Archibald Constable and Co […], →OCLC, stanza X, page 91:

        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; […]

別の表記

• vertual, virtuall (廃れた用法)
• vertuall (廃れた用法, まれに)

派生語

名詞

virtual (countable かつ uncountable, 複数形 virtuals)

1. (uncountable) Preceded by the: that which is imitated or simulated rather than existing in fact or reality; (countable) an instance of this.
   1. (uncountable) That which is simulated in a computer and/or online; virtual reality; (countable) an instance of this; specifically (gambling), a computer simulation of a real-world sport such as horse racing.
2. (countable, programming) A virtual (adjective sense 3.3) member function of a class.

参照

Further reading

• virtual (disambiguation) on Wikipedia.