Meanings
nounPonzo illusion (plural Ponzo illusions)
plural Ponzo illusions
- An optical illusion whereby a horizontal bar looks wider when farther up a picture of railroad tracks than when lower.
Origin
First demonstrated by the Italian psychologist Mario Ponzo (1882–1960) in 1911.
Full word history & related roots →Cite this entry
APA
Ponzo illusion. (n.d.). In WatkinsX Dictionary. Retrieved November 4, 2026, from https://dictionary.watkinsx.com/word/Ponzo%20illusion
MLA
“Ponzo illusion.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/Ponzo%20illusion. Accessed November 4, 2026.
Chicago
WatkinsX Dictionary, s.v. “Ponzo illusion,” accessed November 4, 2026, https://dictionary.watkinsx.com/word/Ponzo%20illusion.
Source: Ponzo illusion on Wiktionary, CC BY-SA 4.0.