aberration n.
1.
A deviation from what is normal, usual, or right. See also
chromosomal aberration
.
2.
A temporary lapse of behaviour or mental function.
3.
A defect of the
crystalline lens
of the eye, or of any other lens or mirror, also called astigmatism or dioptric aberration, in which rays of light do not all converge on to a single focal point. In chromatic aberration, different wavelengths of light are refracted through different angles and focused at ...