lens /lenz/
Noun
1. a piece of curved glass or other transparent material used to focus or disperse light rays "We see the world through the lens of all our experiences; that is a fundamental part of the human condition." - Madeleine Kunin (1933 - ) 2. a part of the eye that focuses light rays to form an image on the retina "The cornea and lens form an optical apparatus of remarkable perfection." - Santiago Ramón y Cajal (1852 - 1934)