tapetum

Pronunciation: tă-pē′tŭm, -tă

Definition:

1. In general, any membranous layer or covering.
2. 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.
3. A dense layer in the choroidea of the eye of many mammalian species, including the cat and dog but not humans, which 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.

Synonym(s): Fielding membrane, membrana versicolor

[L. tapeta, a carpet]

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