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folie de grandeur

American  
[faw-leeduhgrahn-dœr] / fɔ lidəgrɑ̃ˈdœr /
French folie des grandeurs

noun

Psychiatry.

plural

folies de grandeur
  1. a delusion of grandeur; megalomania.


folie de grandeur British  
/ fɔli də ɡrɑ̃dœr /

noun

  1. delusions of grandeur

"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

Etymology

Origin of folie de grandeur

From French

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

De Gaulle's Asian adventure dismayed the overwhelming majority of South Viet Nam's 7,000 strongly anti-Communist overseas Frenchmen, who called it "une folie de grandeur."

From Time Magazine Archive

But Struthers, who is not untouched with her folie de grandeur, has the slightly flurried satisfaction of an exile who has at last come into her own.

From The Prairie Mother by Becher, Arthur E.