from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The blurring of an image that occurs when light from the margin of a lens or mirror with a spherical surface comes to a shorter focus than light from the central portion. The changing focal length is caused by deviations in the lens or mirror surface from a true sphere.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A type of lens aberration which causes blurriness, particularly away from the centre of the lens.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. an optical aberration resulting in a distorted image
Sorry, no etymologies found.