Definition of folie à deux in English:

folie à deux

noun

mass noun
  • Delusion or mental illness shared by two people in close association.

    ‘a classic case of folie à deux’
    count noun ‘she entered a folie à deux with her therapist’
    • ‘The strange dance of recrimination, regret, and new intimacy between these two make Bergman's late-period folies à deux look arid and academic in contrast.’
    • ‘Addicts of flaming folies à deux will be pleased to learn that this season is providing a promisingly thorny set of variations on the theme of really tough love.’
    • ‘They each reinforce each others insanity - in psychology this is called a folie à deux or a shared madness.’
    • ‘As noted above, we could uncover no causative or precipitating emotional or other factors for this folie à deux dissociative disorder.’

Origin

French, literally ‘shared madness’.

Pronunciation

folie à deux

/ˌfɒlɪ a ˈdəː/