ret·i·na

[ret-n-uh, ret-nuh]
noun, plural ret·i·nas, ret·i·nae [ret-n-ee] . Anatomy.
the innermost coat of the posterior part of the eyeball that receives the image produced by the lens, is continuous with the optic nerve, and consists of several layers, one of which contains the rods and cones that are sensitive to light.
Origin:
1350–1400; Middle English ret(h)ina < Medieval Latin rētina, perhaps equivalent to Latin rēt- (stem of rēte) net + -ina -ine1

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a fool or simpleton; ninny.
a stew of meat, vegetables, potatoes, etc.
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Dictionary.com Unabridged

Ret·in-A

[ret-n-ey]
Trademark. a brand of tretinoin, used especially to reduce wrinkles caused by overexposure to the sun.
Origin:
1975–80

Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2013.
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World English Dictionary
retina (ˈrɛtɪnə) [Click for IPA pronunciation guide]
 
—n , pl -nas, -nae
the light-sensitive membrane forming the inner lining of the posterior wall of the eyeball, composed largely of a specialized terminal expansion of the optic nerve. Images focused here by the lens of the eye are transmitted to the brain as nerve impulses
 
[C14: from Medieval Latin, perhaps from Latin rēte net]
 
'retinal
 
—adj

Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
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Etymonline
Word Origin & History

retina
1392, from M.L. retina, probably from V.L. (tunica) *retina, lit. "net-like tunic," on resemblance to the network of blood vessels at the back of the eye, and ult. from L. rete "net." The V.L. phrase may be Gerard of Cremona's 12c. translation of Ar. (tabaqa) sabakiva "netlike layer," itself a translation
of Gk. amphiblestroeides (khiton).
Online Etymology Dictionary, © 2010 Douglas Harper
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American Heritage
Medical Dictionary

retina ret·i·na (rět'n-ə)
n. pl. ret·i·nas or ret·i·nae (rět'n-ē')
The delicate multilayered light-sensitive membrane lining the inner posterior chamber of the eyeball containing the rods and cones and connected by the optic nerve to the brain.

ret'i·nal adj.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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American Heritage
Science Dictionary
retina   (rět'n-ə)  Pronunciation Key 
Plural retinas or retinae (rět'n-ē')
The light-sensitive membrane that lines the inside of the back of the eyeball and connects to the brain by the optic nerve. The retina of vertebrate animals contains rods and cones, specialized cells that absorb light.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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American Heritage
Cultural Dictionary
retina [(ret-n-uh)]

The inner layer of the eye, sensitive to light, that is connected to the brain by the optic nerve. The retina lines the rear of the eye-ball. The lens of the eye focuses waves of light on the retina.

The American Heritage® New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
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Example sentences
The procedure reshapes the cornea by vaporizing cells so that light focuses
  onto the retina properly.
Your retina converts light energy into a nerve impulse that is carried to the
  brain and interpreted.
Anyway, they not only fingerprinted her but gave her a retina scan.
The retina is the inner layer of tissue at the back of the eye.
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