mirage

/mi rahzh"/, n.

1. an optical phenomenon, esp. in the desert or at sea, by which the image of some object appears displaced above, below, or to one side of its true position as a result of spatial variations of the index of refraction of air.

2. something illusory, without substance or reality.

3. (cap.) Mil. any of a series of supersonic, delta-wing, multirole French fighter-bombers.

[1795-1805; < F, equiv. to (se) mir(er) to look at (oneself), be reflected ( < L mirari to wonder at) + -age -AGE]

Syn. 2. illusion, phantom, fancy.

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In optics, the deceptive appearance of a distant object caused by the bending of light rays (refraction) in layers of air of varying density.

Under certain conditions, such as over a stretch of pavement or desert air heated by intense sunshine, the air cools rapidly with elevation and therefore increases in density and refractive power. Sunlight reflected down from the upper portion of an object will be directed through the cool air in the normal way; although the light would not be seen ordinarily because of the angle, it curves upward after it enters the rarefied hot air near the ground, thus being refracted to the observer's eye as though it had originated below the heated surface. When the sky is the object of the mirage, the land is mistaken for a lake or sheet of water.

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▪ airplane

      any member of a family of combat aircraft produced by the Dassault-Breguet aeronautics firm of France. These relatively inexpensive, simple, durable aircraft were adopted by many of the world's smaller air forces from the 1960s. The first Mirage aircraft was the single-engine, delta-wing Mirage III. This craft was first flown in 1956 but subsequently underwent significant development. One variant of it became a basic interceptor, another a fighter-bomber, and a third a reconnaissance aircraft. During the 1960s the Mirage III was the basic air superiority fighter of the Israeli air force, and it performed spectacularly in the Six-Day War of 1967. Other countries whose air forces adopted the Mirage III included Brazil, Lebanon, South Africa, Argentina, Pakistan, Spain, Australia and Switzerland.

      An export version of the Mirage III, called the Mirage 5, was adapted for ground attack and equipped with simplified avionics. It was first flown in 1967 and was sold to Belgium (in a coproduction arrangement), Pakistan, Peru, Colombia, Libya, Abu Dhabi, and Venezuela. The Mirage F-1, a multipurpose fighter developed as a replacement for the Mirage III in the French air force, entered service in 1973. This aircraft lacked the delta-wing design that had characterized all previous Mirages. F-1s were purchased by Greece, Morocco, South Africa, Spain, Jordan, and Iraq, among other countries. The French air force's F-1 was replaced by a newer multipurpose fighter, the Mirage 2000, beginning in 1984. This aircraft once again had a delta-wing design.

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