tapetum

1. In general, any membranous layer or covering. 2. [TA] In neuroanatomy, a thin sheet of fibers in the lateral wall of the temporal and occipital horns of the lateral ventricle, continuous with the corpus callosum. SYN: Fielding membrane, membrana versicolor. 3. A dense layer in the choroidea of the eye of many mammalian species, including the cat and dog but not humans, that forms a discrete or diffuse area of reflective cells, rodlets, and fibers; its strong light-reflecting properties cause the metallic hue and light-glow of such eyes in the dark. [L. tapeta, a carpet]

- t. alveoli SYN: periodontium.

- t. nigrum SYN: pigmented layer of retina.

- t. oculi SYN: pigmented layer of retina.

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ta·pe·tum tə-'pēt-əm n, pl ta·pe·ta -'pēt-ə

1) any of various membranous layers or areas esp. of the choroid and retina of the eye specif TAPETUM LUCIDUM

2) a layer of nerve fibers derived from the corpus callosum and forming part of the roof of each lateral ventricle of the brain

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n.

1. a layer of specialized reflecting cells in the choroid behind the retina of the eye.

2. a band of nerve fibres that form the roof and wall of the lower posterior part of the corpus callosum.

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ta·pe·tum (tə-peґtəm) pl. tapeґta [L., from Gr. tapētion, dim. of tapēs a carpet, rug] 1. a covering structure, or layer of cells. 2. t. corporis callosi.