eyeball

n. globe of the eye within the eyelids and socket

v. eye, stare at in a close manner, scrutinize

adj. established upon observation, on the basis of observation

Eyes are organs of vision that detect light. Different kinds of light-sensitive organs are found in a variety of organisms. The simplest eyes do nothing but detect whether the surroundings are light or dark, while more complex eyes can distinguish shapes and colors. The visual fields of some such complex eyes largely overlap, to allow better depth perception (binocular vision), as in humans; and others are placed so as to minimize the overlap, such as in rabbits and chameleons.
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Eyeball /eye·ball/ the ball or globe of the eye. eye·ball n. 1. The globe-shaped portion of the eye surrounded by the socket and covered externally [more]Eyeball - Community and Resources

Noun
1. the ball-shaped capsule containing the vertebrate eye
(synonym) orb
(hypernym) capsule
(part-holonym) eye, oculus, optic
(derivation) eye
Verb
1. look at
(synonym) eye
(hypernym) look
(derivation) orb

(n.)
The ball or globe of the eye.