mirage

An optical phenomenon that creates the illusion of water, often with inverted reflections of distant objects, and results from distortion of light by alternate layers of hot and cool air.

Something illusory or insubstantial.

An optical illusion due to excessive bending of light-rays in traversing adjacent layers of air of widely different densities, whereby distorted, displaced, or inverted images are produced.

Hence Deceptiveness of appearance; a delusive seeming; an illusion.

An optical effect, sometimes seen on the ocean, but more frequently in deserts, due to total reflection of light at the surface common to two strata of air differently heated. The reflected image is seen, commonly in an inverted position, while the real object may or may not be in sight. When the surface is horizontal, and below the eye, the appearance is that of a sheet of water in which the object is seen reflected; when the reflecting surface is above the eye, the image is seen projected against the sky. The fata Morgana and looming are species of mirage.

An optical phenomenon in which light is refracted through a layer of hot air close to the ground, giving the appearance of there being refuge in the distance.

An illusion.

an optical illusion in which atmospheric refraction by a layer of hot air distorts or inverts reflections of distant objects

something illusory and unattainable