mirage (n.)

"optical illusion of objects reflected in a sheet of water in hot, sandy deserts," 1800, in translations of French works, from French mirage (1753), from se mirer "to be reflected," from Latin mirare (see mirror (n.)). Or the French word is from Latin mirus "wonderful" (see miracle). The similarity to Arabic mi'raj has been noted, but the usual sense of that word is "ladder, stairs; climb, ascent," and the resemblance appears to be coincidental. The standard Arabic for "a desert mirage" is sarāb. The figurative sense of "deceptiveness of appearance, a delusive seeming" is by 1812. The phenomenon is produced by excessive bending of light rays through layers of air of different densities, producing distorted, displaced, or inverted images.