ab·er·ra·tion [ab-uh-rey-shuhn] noun
1. the act of departing from the right, normal, or usual course.
2. the act of deviating from the ordinary, usual, or normal type.
3. deviation from truth or moral rectitude.
4. mental irregularity or disorder, especially of a minor or temporary nature; lapse from a sound mental state.
5. apparent displacement of a heavenly body, owing to the motion of the earth in its orbit.
6. any disturbance of the rays of a pencil of light such that they can no longer be brought to a sharp focus or form a clear image.
7. a defect in a camera lens or lens system, due to flaws in design, material, or construction, that can distort the image.


1585–95; < Latin aberrātiōn- (stem of aberrātiō ), equivalent to aberrāt ( us ), past participle of aberrāre (see aberrant) + -iōn- -ion

Related forms

ab·er·ra·tion·al, adjective

Other Meanings

World English Dictionary

aberration (ˌæbəˈreɪʃən)

— n
1. deviation from what is normal, expected, or usual
2. departure from truth, morality, etc
3. a lapse in control of one's mental faculties

Medical Dictionary

aberration ab·er·ra·tion (āb'ə-rā'shən)

A departure from the normal or typical.

A psychological disorder or abnormal alteration in one's mental state.

A defect of focus, such as blurring in an image.

An imperfect image caused by a physical defect in an optical element, as in a lens.

A deviation in the normal genetic structure or number of chromosomes in an organism.

Science Dictionary

aberration (āb'ə-rā'shən)
A deviation in the normal structure or number of chromosomes in an organism.

A defect in a lens or mirror that prevents light rays from being focused at a single point and results in a distorted or blurred image. ◇ Aberration that results in distortion of color is called chromatic aberration. ◇ Aberration that is caused by imperfections in the surface or shape of a spherical mirror or lens is called spherical aberration.