Müller-Lyer illusion

[ muhl-er-lahy-er, myoo-ler-, mil-er-; German myl-uhr-lee-uhr ]

/ ˈmʌl ərˈlaɪ ər, ˈmyu lər-, ˈmɪl ər-; German ˈmül ərˈli ər /

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noun

a geometric illusion in which two lines of equal length appear unequal depending on whether angular lines forming arrowheads at each end point toward or away from each other.

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Origin of Müller-Lyer illusion

After Franz-Karl Müller-Lyer (1857–1916), German sociologist, who described the illusion in 1889

Words nearby Müller-Lyer illusion

muller, mullered, müllerian, müllerian duct, Müllerian mimicry, Müller-Lyer illusion, mullet, mulley, mulligan, mulligatawny, mulligrubs

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use Müller-Lyer illusion in a sentence

In Aug. 2003, Muller said he believed Cobalt was merely a holding facility.
Inside the CIA’s Sadistic Dungeon|Tim Mak|December 9, 2014|DAILY BEAST
Traditional coach seats gave the illusion of comfortable padding but were angular, not reflecting body shapes.
Flying Coach Is the New Hell: How Airlines Engineer You Out of Room|Clive Irving|November 25, 2014|DAILY BEAST
And we are under no illusion that this state of affairs is confined to one battalion.
Corruption Eats Away at Ukraine Military|Charles McPhedran|October 21, 2014|DAILY BEAST
You said, “freedom of speech is an illusion” and “freedom of assembly is an illusion.”
Julian Casablancas Enters the Void: On the Strokes’ Friction, Why He Left NYC, and Starting Over|Marlow Stern|October 9, 2014|DAILY BEAST

Democracy is an illusion, freedom of speech is an illusion, freedom of assembly is an illusion.
Julian Casablancas Enters the Void: On the Strokes’ Friction, Why He Left NYC, and Starting Over|Marlow Stern|October 9, 2014|DAILY BEAST
But the growing crops are too cleanly and carefully weeded and too uniformly good to protract the illusion.
Glances at Europe|Horace Greeley
All this I admit to be the fever of the mind—a waking dream—an illusion to which mesmerism or magic is but a frivolity.
Blackwood's Edinburgh Magazine, No. CCCXXXIX. January, 1844. Vol. LV.|Various
The burning atmosphere, the motionless air caused doubtless the optical illusion.
The Wave|Algernon Blackwood
Nor wilt thou rest forever, weary heart.The last illusion is destroyed,That I eternal thought.
The Poems of Giacomo Leopardi|Giacomo Leopardi
From the first entrance, to the last cry of triumph or despair, the illusion was perfect.
The Life & Letters of Peter Ilich Tchaikovsky|Modeste Tchaikovsky

British Dictionary definitions for Müller-Lyer illusion

Müller-Lyer illusion

/ (ˈmuːləˈlaɪə) /

noun

an optical illusion in which a line with inward pointing arrowheads is seen as longer than an equal line with outward pointing arrowheads

Word Origin for Müller-Lyer illusion

C19: named after Franz Müller-Lyer (1857–1916), German sociologist and psychiatrist

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012