retina

noun
ret·​i·​na | \ ˈre-tə-nə How to pronounce retina (audio) , ˈret-nə \
plural retinas also retinae\ ˈre-​tə-​ˌnē How to pronounce retina (audio) , -​ˌnī \

Definition of retina

: 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

Examples of retina in a Sentence

Recent Examples on the Web The first layer of neurons in the retina are the photoreceptors. Gabriel A. Silva, Forbes, 20 May 2021 The latter can use higher laser power because the human cornea absorbs light at this wavelength, limiting damage to the retina. Sabbir Rangwala, Forbes, 28 May 2021 Retinitis pigmentosa, which impacts more than two million people around the world, causes the light-sensitive cells on the surface of the retina to die, reports James Gallagher for BBC News. Alex Fox, Smithsonian Magazine, 25 May 2021 So the scientists chose an optogenetic protein that’s sensitive only to amber light, which is easier on the eye than other colors, and used viruses to deliver these amber proteins to the ganglion cells in the retina. BostonGlobe.com, 24 May 2021 Some say the sense relies on cells containing a magnetic iron mineral, magnetite, whereas others invoke a protein in the retina called cryptochrome. Nikk Ogasa, Science | AAAS, 6 May 2021 These copies are encased in a safe virus that breaks through the cells of the retina, then initiates the production of the RPE65 protein that allows for healthy eyesight. orlandosentinel.com, 16 May 2021 Mead immediately lost vision in the right eye, was taken to OHSU Hospital for immediate examination and later returned for surgery to repair a hole in her right retina, according to her attorneys. oregonlive, 4 May 2021 The congressman underwent emergency surgery at DeBakey VA Medical Center in Houston to reattach his left retina. Kristin Wilson And Paul Leblanc, CNN, 29 Apr. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'retina.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of retina

14th century, in the meaning defined above

History and Etymology for retina

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

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Time Traveler for retina

Time Traveler

The first known use of retina was in the 14th century

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Statistics for retina

Last Updated

14 Jun 2021

Cite this Entry

“Retina.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/retina. Accessed 17 Jun. 2021.

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More Definitions for retina

retina

noun

English Language Learners 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

retina

noun
ret·​i·​na | \ ˈre-tə-nə How to pronounce retina (audio) \
plural retinas also retinae\ -​ˌnē \

Kids Definition of retina

: 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

retina

noun
ret·​i·​na | \ ˈret-ᵊn-ə, ˈret-nə How to pronounce retina (audio) \
plural retinas also retinae\ -​ᵊn-​ˌē How to pronounce retina (audio) \

Medical Definition of retina

 (Entry 1 of 2)

: 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

Retin-A

trademark
Ret·​in-A | \ ˌret-ᵊn-ˈā How to pronounce Retin-A (audio) \

Medical Definition of Retin-A (Entry 2 of 2)

used for a preparation of tretinoin

More from Merriam-Webster on retina

Nglish: Translation of retina for Spanish Speakers

Britannica English: Translation of retina for Arabic Speakers

Britannica.com: Encyclopedia article about retina

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