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

Doing something your brain tells you is structurally impossible was like inhabiting an optical illusion and we all laughed as we scaled the multi-tiered falls with the occasional assistance of a tethered rope.

From The Wall Street Journal • Jan. 28, 2026

She had lost weight and at first I thought she might have grown, because she looked taller, but then I realized it was just an optical illusion, the effect of my own shrinking.

From "The House of the Spirits: A Novel" by Isabel Allende