noun ab·er·ra·tion \ˌa-bə-ˈrā-shən\

Definition of aberration

  1. 1a :  the fact or an instance of deviating or being aberrant especially from a moral standard or normal state aberrations of characterb :  something or someone regarded as atypical and therefore able be ignored or discounted Harkins was to be regarded as an aberration among American military leaders … — Neil Sheehan The U.S. establishment treated this grassroots movement almost as an aberration, virtually ignoring it. — Helen Caldicott As for Putin's desire to lay waste to Chechnya, Western leaders largely dismiss it as an aberration … — The New Republic

  2. 2 :  failure of a mirror, refracting surface, or lens to produce exact point-to-point correspondence between an object and its image chromatic aberration … the telescope suffers from a serious focusing problem, a condition known as spherical aberration, which causes the point-like images of stars to be surrounded by fuzzy haze. — M. Mitchell Waldrop

  3. 3 :  unsoundness or disorder of the mind

  4. 4 :  a small periodic change of apparent position in celestial bodies due to the combined effect of the motion of light and the motion of the observer

  5. 5 :  an aberrant individual


play \-shnəl, -shə-nəl\ adjective aberrational behavior They react, often in anger, to particular decisions but tend to regard them as aberrational rather than systemic failures. — Robert H. Bork

Examples of aberration in a sentence

  1. Recently geneticists have taken a closer look at a genetic aberration previously considered rare …  . The genes may be perfectly normal, yet there is a shortage or surplus of DNA sequences that may play a role in diseases that defy straightforward genetic patterns … —Melinda Wenner, Scientific American, June 2009

  2. He did hit five homers for Texas in 1987, but that was an aberration. In no other major league season has he hit more than three, and last season he actually came up with a goose egg. —E. M. Swift, Sports Illustrated, 5 Apr. 1989

  3. Gilliard's studies of numerous bird of paradise species brought them from the realm of exotic aberrations to the forefront of sociobiology. —Jared M. Diamond, Nature, 24-30 Sept. 1981

  4. For her, such a low grade on an exam was an aberration.

  5. a study of sexual aberration

Origin and Etymology of aberration

Latin aberrare —see 1aberrant

First Known Use: 1588

ABERRATION Defined for Kids


noun ab·er·ra·tion \ˌa-bə-ˈrā-shən\

Definition of aberration for Students

  1. :  an instance of being different from what is normal or usual The poor test grade was an aberration for her.

Medical Dictionary


noun ab·er·ra·tion \ˌab-ə-ˈrā-shən\

Medical Definition of aberration

  1. 1:  failure of a mirror, refracting surface, or lens to produce exact point-to-point correspondence between an object and its image

  2. 2:  unsoundness or disorder of the mind

  3. 3:  an aberrant organ or individual


\-shnəl, -shən-əl\play adjective

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