Delboeuf illusion

noun

An optical illusion of relative size perception, usually illustrated by two discs of identical size, one of which is surrounded by a ring.

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Meanings

nounDelboeuf illusion (plural Delboeuf illusions)

plural Delboeuf illusions

  1. An optical illusion of relative size perception, usually illustrated by two discs of identical size, one of which is surrounded by a ring.

Origin

Discovered in 1865 by the Belgian scientist Joseph Remi Leopold Delboeuf (1831–1896).

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Cite this entry
APA

Delboeuf illusion. (n.d.). In WatkinsX Dictionary. Retrieved November 4, 2026, from https://dictionary.watkinsx.com/word/Delboeuf%20illusion

MLA

“Delboeuf illusion.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/Delboeuf%20illusion. Accessed November 4, 2026.

Chicago

WatkinsX Dictionary, s.v. “Delboeuf illusion,” accessed November 4, 2026, https://dictionary.watkinsx.com/word/Delboeuf%20illusion.

Source: Delboeuf illusion on Wiktionary, CC BY-SA 4.0.