Lexic.us

Definition of Retina

1. Noun. The innermost light-sensitive membrane covering the back wall of the eyeball; it is continuous with the optic nerve.

Definition of Retina

1. n. The delicate membrane by which the back part of the globe of the eye is lined, and in which the fibers of the optic nerve terminate. See Eye.

Definition of Retina

1. Noun. (anatomy) The thin layer of cells at the back of the eyeball where light is converted into neural signals sent to the brain. ¹

¹ Source: wiktionary.com

Definition of Retina

1. a membrane of the eye [n -NAS or -NAE]

Medical Definition of Retina

1. Light sensitive layer of the eye. In vertebrates, looking from outside, there are four major cell layers: (i) the outer neural retina, which contains neurons (ganglion cells, amacrine cells, bipolar cells) as well as blood vessels, (ii) the photoreceptor layer, a single layer of rods and cones, (iii) the pigmented retinal epithelium (PRE or RPE), (iv) the choroid, composed of connective tissue, fibroblasts and including a well vascularised layer, the chorio capillaris, underlying the basal lamina of the PRE. Behind the choroid is the sclera, a thick organ capsule. In molluscs (especially cephalopods such as the squid) the retina has the light sensitive cells as the outer layer with the neural and supporting tissues below. See: retinal rods, retinal cones, rhodopsin. This entry appears with permission from the Dictionary of Cell and Molecular Biology (11 Mar 2008)

Lexicographical Neighbors of Retina

Literary usage of Retina

Below you will find example usage of this term as found in modern and/or classical literature:

1. Encyclopaedia Britannica: A Standard Work of Reference in Art, Literature (1907)
"SPECIFIC INFLUENCE OF LIGHT ON THE retina. The retina is the terminal organ of vision, and all the parts in front of it are merely optical arrangements for ..."

2. The Encyclopaedia Britannica: “a” Dictionary of Arts, Sciences, Literature edited by Hugh Chisholm (1911)
"It is possible that the retina, by which is meant all the layers except those on ... If a frog be killed in the dark, and if its retina be exposed only to ..."

3. Psychology: General Introduction by Charles Hubbard Judd (1907)
"The areas intermediate between the extreme periphery of the retina and the center of clear ... Shows a diagrammatic section of the retina. After Greeff. ..."

4. A Text-book of Physiology for Medical Students and Physicians by William Henry Howell (1911)
"The Portion of the retina Stimulated by Light.—The normal stimulus to the sensory cells in the retina is found in the vibrations of the ether, ..."

5. A Text-book of Physiology for Medical Students and Physicians by William Henry Howell (1911)
"The normal stimulus to the sensory cells in the retina is found in the vibrations of the ether, the waves of light. When sunlight is passed through a prism ..."

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