[1] : The Collaborative International Dictionary of English v.0.48

eye-spot \eye"-spot`\, n. zo"ol.
   a a simple visual organ found in many invertebrates,
       consisting of pigment cells covering a sensory nerve
       termination.
   b an eyelike spot of color.
       1913 webster

[2] : WordNet (r) 2.0

eyespot
     n : an eyelike marking as on the wings of some butterflies;
         usually a spot of color inside a ring of another color
         syn: ocellus
see also:
ocellus 

Eyespot >> E Words
Eyespot, definition of term: Eyespot
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