optical illusion

American  

noun

1. illusion4

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optical illusion British  

noun

1. an object causing a false visual impression

2. an instance of deception by such an object

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Etymology

Origin of optical illusion

First recorded in 1785–95

Example Sentences

The saber-toothed cat that appears mirage-like through a window, an optical illusion known as a Pepper’s Ghost, doesn’t reflect modern knowledge of the animal’s anatomy.

From Los Angeles Times • Jun. 6, 2026

By presenting Satan's fall as a violent physical event instead of a purely spiritual allegory or optical illusion, Dante may have helped move Western thought toward the idea that celestial objects can directly reshape Earth.

From Science Daily • May 11, 2026

This is actually something of an optical illusion, for the options are not getting more expensive in terms of price as the earnings date approaches.

From MarketWatch • Apr. 9, 2026

Scotland fans on social media have compared the new away jersey to the optical illusion dress that became an internet sensation in 2015.

From BBC • Mar. 24, 2026

“Please, step right on through. The rock is an optical illusion, a very well-crafted hologram.”

From "Glitch" by Laura Martin