Princeton's WordNet(0.00 / 0 votes)Rate this definition: 1  shimmer, play(verb) a weak and tremulous light. 2  shimmer(verb) shine with a weak or fitful light. 3  shimmer(verb) give off a shimmering reflection, as of silk.
CONE CELLS are the second type of light sensitive cells in the retina of the eye. The human retina contains 6-7 million cones; they function best in bright light and are essential for acute vision (receiving a sharp accurate image).
Rods are more sensitive to light than cones, but cones are important for color vision. astigmatism A curvature defect of the lens or cornea in which some parts of an image are in focus on the retina and other parts are blurred and vision is distorted is called