aberration

1 a serious mental disorder that prevents one from living a safe and normal life <Joan of Arc was certain the voices she had been hearing were not a manifestation of some sort of aberration> Synonyms insanity, dementia, derangement, lunacy, madness, mania, rage [archaic]Related Words neurosis, psychosis; instability, irrationality, unreasonableness; delirium, frenzy, hysteria; hallucinosis, hypomania, paranoia, schizophrenia; senile dementia; delusion, hallucination; monomania, obsession, phobia; abnormality, dementedness, unsoundnessNear Antonyms lucidity, rationality, rationalness, reasonability, reasonableness; normality, soundnessAntonyms mind, saneness, sanity

2 something that is different from what is ordinary or expected <there are some slight aberrations in the type due to the nature of old printing presses> Synonyms anomaly, abnormality, exception, oddity, oddment, rarityRelated Words curiosity, peculiarity, singularity; accident, bizarrerie, phenomenon, quirk, vagary; distortion, kink, mutation, variation; difference, disparity, inconsistence, inconsistency; error, mistake; contradiction, paradoxNear Antonyms norm, ordinary, usual