visual system - the sensory system for vision

sense modality, sensory system, modality - a particular sense

exteroception - sensitivity to stimuli originating outside of the body

stigmatism - normal eyesight

achromatic vision - vision using the rods

acuity, sharp-sightedness, visual acuity - sharpness of vision; the visual ability to resolve fine detail (usually measured by a Snellen chart)

binocular vision - vision involving the use of both eyes

central vision - vision using the fovea and parafovea

chromatic vision, color vision, trichromacy - the normal ability to see colors

distance vision - vision for objects that a 20 feet or more from the viewer

eyesight, sightedness, seeing - normal use of the faculty of vision

monocular vision - vision with only one eye

near vision - vision for objects 2 feet or closer to the viewer

night vision, night-sight, scotopic vision, twilight vision - the ability to see in reduced illumination (as in moonlight)

daylight vision, photopic vision - normal vision in daylight; vision with sufficient illumination that the cones are active and hue is perceived

peripheral vision - vision using only the periphery of the retina