Wiktionary
folie de grandeur
n. delusion of grandeur
Usage examples of "folie de grandeur".
It's the reverse of what the Freudians call the inferiority complex, a form of egomania, a variety of folie de grandeur.
I mean if I'm not who will be, the state Oscar's in with these medications he's on it's all bursting out in some sort of folie de grandeur, I'm sure you had a taste of it when you were out here last week and I'm really quite surprised to see you back.