n. pl. ret·i·nas or ret·i·nae (rĕtn-ē′)
A delicate, multilayered, light-sensitive membrane lining the inner eyeball and connected by the optic nerve to the brain.
[Middle English, from Medieval Latin rētina, from Latin rēte, net.]
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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