'Megalomania' definitions:

Definition of 'megalomania'

(from WordNet)
noun
A psychological state characterized by delusions of grandeur

Definition of 'Megalomania'

From: GCIDE
  • Megalomania \Meg`a*lo*ma"ni*a\, n. [NL., fr. megalo- + mania.] (Pathol.) A form of mental alienation in which the patient has grandiose delusions. [1913 Webster] megalomaniacal