Virtual
Virtual Vir"tu*al (?; 135), a. [Cf. F. virtuel. See {Virtue}.] 1. Having the power of acting or of invisible efficacy without the agency of the material or sensible part; potential; energizing. [1913 Webster]

Heat and cold have a virtual transition, without communication of substance. --Bacon. [1913 Webster]

Every kind that lives, Fomented by his virtual power, and warmed. --Milton. [1913 Webster]

2. Being in essence or effect, not in fact; as, the virtual presence of a man in his agent or substitute. [1913 Webster]

A thing has a virtual existence when it has all the conditions necessary to its actual existence. --Fleming. [1913 Webster]

To mask by slight differences in the manners a virtual identity in the substance. --De Quincey. [1913 Webster]

{Principle of virtual velocities} (Mech.), the law that when several forces are in equilibrium, the algebraic sum of their virtual moments is equal to zero.

{Virtual focus} (Opt.), the point from which rays, having been rendered divergent by reflection of refraction, appear to issue; the point at which converging rays would meet if not reflected or refracted before they reach it.

{Virtual image}. (Optics) See under {Image}.

{Virtual moment} (of a force) (Mech.), the product of the intensity of the force multiplied by the virtual velocity of its point of application; -- sometimes called {virtual work}.

{Virtual velocity} (Mech.), a minute hypothetical displacement, assumed in analysis to facilitate the investigation of statical problems. With respect to any given force of a number of forces holding a material system in equilibrium, it is the projection, upon the direction of the force, of a line joining its point of application with a new position of that point indefinitely near to the first, to which the point is conceived to have been moved, without disturbing the equilibrium of the system, or the connections of its parts with each other. Strictly speaking, it is not a velocity but a length.

{Virtual work}. (Mech.) See {Virtual moment}, above. [1913 Webster]

The Collaborative International Dictionary of English. 2000.

Synonyms:

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• Virtual — y virtualidad, lo opuesto a lo real y a la realidad, pueden referirse a: Partícula virtual Temperatura virtual Realidad virtual Mundos virtuales Imagen virtual Función virtual Sexo virtual Mascota virtual Bien virtual Herencia virtual… …   Wikipedia Español

• virtual — vir‧tu‧al [ˈvɜːtʆuəl ǁ ˈvɜːr ] adjective [only before a noun] 1. a virtual monopoly, ban, takeover etc is so nearly a complete monopoly, ban etc that any difference is unimportant: • They enjoy a virtual monopoly in sales of pickup trucks. •… …   Financial and business terms

• virtual — VIRTUÁL, Ă, virtuali, e, adj. Care există numai ca posibilitate, Fără a se produce (încă) în fapt; al cărui efect este potenţial, şi nu actual. ♢ Imagine virtuală = imagine în care punctele convergente se găsesc în prelungirea razelor de lumină… …   Dicționar Român

• virtual — has taken on a brand new meaning in the computer age. By itself it is defined somewhat obscurely as ‘not physically existing as such but made by software to appear to exist’, and it only begins to make sense in its most common context of virtual… …   Modern English usage

• virtual — I adjective basic, capable, constructive, deep down, deep rooted, deep seated, equivalent, essential, fundamental, implicit, indirect, inherent, intrinsic, material, potent, potential, powerful, practical, substantive, tantamount to, underlying,… …   Law dictionary

• virtual — (Del lat. virtus, fuerza, virtud). 1. adj. Que tiene virtud para producir un efecto, aunque no lo produce de presente, frecuentemente en oposición a efectivo o real. 2. Implícito, tácito. 3. Fís. Que tiene existencia aparente y no real. ☛ V. foco …   Diccionario de la lengua española

• virtual — [vʉr′cho͞o əl] adj. [ME vertual < ML virtualis < L virtus, strength, VIRTUE] 1. being such practically or in effect, although not in actual fact or name [a virtual impossibility] 2. Comput. a) designating or of a kind of MEMORY (sense 8 b)… …   English World dictionary

• virtual — adj. 2 g. 1. Que existe potencialmente e não em ação. 2. Suscetível de se realizar ou de se exercer. = POSSÍVEL, POTENCIAL 3. Equivalente a outro. = ANALÓGICO 4. Que é feito ou simulado através de meios eletrônicos. 5.  [Física] Que se forma num… …   Dicionário da Língua Portuguesa

• Virtual — (Virtuell, v. lat.), 1) kräftig, vermögend; 2) der Kraft od. Bedeutung nach, seinem Wesen nach geltend …   Pierer's Universal-Lexikon

• virtual —   [engl.], virtuell. * * * vir|tu|al <Adj.> (veraltet): virtuell …   Universal-Lexikon