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

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

From MarketWatch • Mar. 26, 2026

It turns out that the abundant free cash flow that Meta reports to investors is something of an optical illusion.

From The Wall Street Journal • Feb. 23, 2026

Or that optical illusion with the staircases that never stop going upward.

From "P.S. I Miss You" by Jen Petro-Roy