Aberration

the act of departing from the right, normal, or usual course.
the act of deviating from the ordinary, usual, or normal type.
deviation from truth or moral rectitude.
mental irregularity or disorder, especially of a minor or temporary nature; lapse from a sound mental state.
Astronomy. apparent displacement of a heavenly body, owing to the motion of the earth in its orbit.
Optics. 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.
Photography. a defect in a camera lens or lens system, due to flaws in design, material, or construction, that can distort the image.
Contemporary Examples

It seemed like an aberration, not a pattern to be worried about.
The Last Columbine Mystery Dave Cullen February 23, 2010

The Shalit trade is not an aberration, but a reflection of Israeli insularity that has grown stronger in recent months and years.
Shalit Was Worth It Micah Stein July 19, 2012

His actions may have been an aberration but his thinking, sadly, is not.
How To Take Purim Seriously Shaul Magid February 20, 2013

But as the report pointed out time and time again, that dark era of violence in America was not some aberration.
Sorry, But Don’t Expect Any Change After Newtown Buzz Bissinger December 16, 2012

That attack is looking disturbingly more like a sign of things to come than an aberration.
Right-Wing Terror Returns Benjamin Sarlin June 9, 2009

Historical Examples

Doubtless the young man had already seen his error; and really, putting aside that one aberration, he was very nice!
That Unfortunate Marriage, Vol. 2(of 3) Frances Eleanor Trollope

But no sooner had it done so, than he understood it was an aberration on his part.
Mystics and Saints of Islam Claud Field

It is found that this point is intimately connected with the phenomenon of aberration.
The Story of the Heavens Robert Stawell Ball

A simple rule will find the position of the star due to aberration.
The Story of the Heavens Robert Stawell Ball

His call to the ministry was a phenomenon, an aberration of adolescence.
Thirty Howard Vincent O’Brien

noun
deviation from what is normal, expected, or usual
departure from truth, morality, etc
a lapse in control of one’s mental faculties
(optics) a defect in a lens or mirror that causes the formation of either a distorted image or one with coloured fringes See also spherical aberration, chromatic aberration
(astronomy) the apparent displacement of a celestial body due to the finite speed of light and the motion of the observer with the earth
n.

1590s, “a wandering, straying,” from Latin aberrationem (nominative aberratio) “a wandering,” noun of action from past participle stem of aberrare “to wander out of the way, lose the way, go astray,” from ab- “away” (see ab-) + errare “to wander” (see err). Meaning “deviation from the normal type” first attested 1846.

aberration ab·er·ra·tion (āb’ə-rā’shən)
n.

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.

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. See also astigmatism, coma.2