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/ˈmʌl ərˈlaɪ ər, ˈmyu lər-, ˈmɪl ər-;
ˈmül ərˈli ər/
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.
(1857-1916), German sociologist, who described the illusion in 1889
Based on the Random House Dictionary, © Random House, Inc. 2016.
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British Dictionary definitions for
an optical illusion in which a line with inward pointing arrowheads is seen as longer than an equal line with outward pointing arrowheads
C19: named after Franz
(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
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