- spherical aberration
- Aberration Ab`er*ra"tion, n. [L. aberratio: cf. F. aberration.
See {Aberrate}.]
1. The act of wandering; deviation, especially from truth or
moral rectitude, from the natural state, or from a type.
``The aberration of youth.'' --Hall. ``Aberrations from
theory.'' --Burke.
[1913 Webster]
2. A partial alienation of reason. ``Occasional aberrations of intellect.'' --Lingard. [1913 Webster]
Whims, which at first are the aberrations of a single brain, pass with heat into epidemic form. --I. Taylor. [1913 Webster]
3. (Astron.) A small periodical change of position in the stars and other heavenly bodies, due to the combined effect of the motion of light and the motion of the observer; called {annual aberration}, when the observer's motion is that of the earth in its orbit, and daily or {diurnal aberration}, when of the earth on its axis; amounting when greatest, in the former case, to 20.4'', and in the latter, to 0.3''. {Planetary aberration} is that due to the motion of light and the motion of the planet relative to the earth. [1913 Webster]
4. (Opt.) The convergence to different foci, by a lens or mirror, of rays of light emanating from one and the same point, or the deviation of such rays from a single focus; called {spherical aberration}, when due to the spherical form of the lens or mirror, such form giving different foci for central and marginal rays; and {chromatic aberration}, when due to different refrangibilities of the colored rays of the spectrum, those of each color having a distinct focus. [1913 Webster]
5. (Physiol.) The passage of blood or other fluid into parts not appropriate for it. [1913 Webster]
6. (Law) The producing of an unintended effect by the glancing of an instrument, as when a shot intended for A glances and strikes B. [1913 Webster]
Syn: Insanity; lunacy; madness; derangement; alienation; mania; dementia; hallucination; illusion; delusion. See {Insanity}. [1913 Webster]
The Collaborative International Dictionary of English. 2000.