- The iridescent choroid membrane in the eye of certain animals, as the cat.
- A layer of fibers from the corpus callosum forming a portion of the roof of each lateral ventricle of the brain.
Origin of tapetum
- Medieval Latin tapētum coverlet from Latin tapēte, *tapētum from Greek tapēs tapēt- tapestry
From American Heritage Dictionary of the English Language, 5th Edition