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retina

play
noun ret·i·na \ˈre-tə-nə, ˈret-nə\

Simple Definition of retina

  • : the sensitive tissue at the back of the eye that receives images and sends signals to the brain about what is seen

Full Definition of retina

plural retinas or ret·i·nae play \-ˌnē, -ˌnī\

  1. :  the sensory membrane that lines the eye, is composed of several layers including one containing the rods and cones, and functions as the immediate instrument of vision by receiving the image formed by the lens and converting it into chemical and nervous signals which reach the brain by way of the optic nerve — see eye illustration

Origin of retina

Middle English rethina, from Medieval Latin retina, probably from Latin rete net


First Known Use: 14th century


Medical Dictionary

retina

play
noun ret·i·na \ˈret-ən-ə, ˈret-nə\

Medical Definition of retina

plural retinas also ret·i·nae \-ən-ˌē\play

  1. :  the sensory membrane that lines most of the large posterior chamber of the vertebrate eye, is composed of several layers including one containing the rods and cones, and functions as the immediate instrument of vision by receiving the image formed by the lens and converting it into chemical and nervous signals which reach the brain by way of the optic nerve



Illustration of retina



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