retina

noun ret·i·na \ ˈre-tə-nə , ˈret-nə \
Updated on: 6 Dec 2017

Definition of retina

plural retinas also retinae play \ˈre-tə-ˌnē, -ˌnī\
: 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

Recent Examples of retina from the Web

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Origin and Etymology of retina

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


RETINA Defined for English Language Learners

retina

noun

Definition of retina for English Language Learners

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


RETINA Defined for Kids

retina

noun ret·i·na \ ˈre-tə-nə \

Definition of retina for Students

plural retinas also retinae \-ˌnē\
: the membrane that lines the back part of the eyeball, contains the rods and cones, and converts the images received by the lens into signals that are transmitted to the brain

Medical Dictionary

retina

noun ret·i·na \ ˈret-ᵊn-ə, ˈret-nə \

medical Definition of retina

plural retinas also retinae play \-ᵊn-ˌē\
: 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


Retin-A

trademark Ret·in-A \ ˌret-ᵊn-ˈā \

medical Definition of Retin-A

used for a preparation of tretinoin


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