folie à deux

[ fo-lee uh -doo; French faw-lee a -dœ ]
/ fɒˈli ə ˈdu; French fɔ li a ˈdœ /

noun, plural fo·lies à deux [fo-leez uh -doo; French faw-lee za -dœ]. /fɒˈliz ə ˈdu; French fɔ li za ˈdœ/. Psychiatry.

the sharing of delusional ideas by two people who are closely associated.



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Origin of folie à deux

Borrowed into English from French around 1890–95 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

British Dictionary definitions for folie à deux

folie à deux
/ (ˈfɒlɪ æ ˈdɜː) /


psychiatry mental illness occurring simultaneously in two intimately related persons who share some of the elements of the illness, such as delusions

Word Origin for folie à deux

French: madness involving two (people)
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

Medical definitions for folie à deux

folie á deux
[ fô-lē′ ä dœ, fŏl′ē ]


A condition in which symptoms of a mental disorder occur simultaneously in two individuals who share a close relationship or association.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.