folie à deux
/ˈfɒli ə ˈdɜː/
folie à deux noun: a situation in which two people behave abnormally together in a way that neither of them would individually.
Noun
folie à deux (plural folies à deux)
- A situation in which two people behave abnormally together in a way that neither of them would individually.
- And so it came to pass. Ann’s psychiatrist at the time came to believe that the pair were psychotic, and diagnosed Ann with folie à deux, a disorder where two people reinforce each other’s mental illness until it reaches extreme proportions.2025 October 8, Stuart Heritage, “‘Their chemistry made one of their deaths inevitable’: how a billionaire couple’s life in paradise turned deadly”, in The Guardian, →ISSN
- A rare syndrome in which a symptom of psychosis (particularly a paranoid or delusional belief) is transmitted from one person to another.
Forms of folie à deux
| plural | folies à deux |
|---|---|
| alternative form | folie a deux |
| alternative form (rare) | folly à deux |
| alternative form (rare) | folly a deux |
Origin of folie à deux
Borrowed from French folie à deux (“madness for/of two [people]”).
Questions about folie à deux
- What does folie à deux mean?
- Folie à deux means a situation in which two people behave abnormally together in a way that neither of them would individually.
- What part of speech is folie à deux?
- Folie à deux is a noun.
- How do you pronounce folie à deux?
- Folie à deux is pronounced /ˈfɒli ə ˈdɜː/.
- What is the plural of folie à deux?
- The plural of folie à deux is folies à deux.
Words near folie à deux in the dictionary
Source and license
Adapted from Wiktionary: folie à deux (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.
Last updated:
Cite this entry: “folie à deux.” Word.ws, https://word.ws/folie_%C3%A0_deux. Based on Wiktionary, CC BY-SA 4.0.