folie à deux

noun

fo·lie à deux fȯ-lē-ä-ˈdœ

ˌfä-lē-ˌä-ˈdər

-ˈdə

: the presence of the same or similar delusional ideas in two persons closely associated with one another

Word History

Etymology

French, literally, double madness

First Known Use

circa 1892, in the meaning defined above

Time Traveler

The first known use of folie à deux was circa 1892

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folic acid

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folie de grandeur

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Style

“Folie à deux.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/folie%20%C3%A0%20deux. Accessed 31 Oct. 2025.

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Medical Definition

folie à deux

noun

-(ˌ)ä-ˈdœ̅, -ˈdə

plural folies à deux

ˌfō-ˈlē(z)-(ˌ)ä-

: the presence of the same or similar delusional ideas in two persons closely associated with one another

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folie à deux

noun

Word History

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