Definition of "lens" []

• A ground or molded piece of glass, plastic, or other transparent material with opposite surfaces either or both of which are curved, by means of which light rays are refracted so that they converge or diverge to form an image. (noun)
• A combination of two or more such pieces, sometimes with other optical devices such as prisms, used to form an image for viewing or photographing. Also called compound lens. (noun)
• A device that causes radiation other than light to converge or diverge by an action analogous to that of an optical lens. (noun)
• A transparent, biconvex body of the eye between the iris and the vitreous humor that focuses light rays entering through the pupil to form an image on the retina. (noun)
• Informal To make a photograph or movie of. (verb-transitive)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "I am wondering if a lens is a little loose and it falls back where it should be when it it lying flat … I was stunned how sharp the images were!"
• "Dave, the lens is the most important factor in close up/macro photography. any used dslr outfitted with the right lens will work for you."
• "If the lens is a wide angle, the birds could seem waaaaaay out there."