adjective
- affectedly grand or important; pompous: grandiose words.
- more complicated or elaborate than necessary; overblown: a grandiose scheme.
- grand in an imposing or impressive way.
- Psychiatry. having an exaggerated belief in one’s importance, sometimes reaching delusional proportions, and occurring as a common symptom of mental illnesses, as manic disorder.
adjective
- pretentiously grand or stately
- imposing in conception or execution
1814, from French grandiose (see grandiose) + -ity.
The author now and then makes a word for his own use, as complicate, for complicated; and, still less fortunately ‘grandiosity’ (p. 343). [review of Joseph Forsyth's "Remarks on Italy," "Edinburgh Review," January 1814]
1828 (earlier as a French word in English), from French grandiose “impressive” (18c.), from Italian grandioso, from Latin grandis “big” (see grand (adj.)). Related: Grandiosely.