1. craziness Of these terms insanity is the most exact and comprehensive, including in its widest sense all morbid conditions of mind due to diseased action of the brain or nervous system, but in its more frequ Synonyms: insanity, aberration, delirium, frenzy, madness, alienation, dementia, hallucination, mania, craziness, derangement, lunacy, monomania Antonyms: clearness, good sense, lucidity, rationality, sanity