Word Study
tapetum
CIDE DICTIONARY
tapetum, n. [NL., from L. tapete a carpet, a tapestry.].
An area in the pigmented layer of the choroid coat of the eye in many animals, which has an iridescent or metallic luster and helps to make the eye visible in the dark. Sometimes applied to the whole layer of pigmented epithelium of the choroid. [1913 Webster]
OXFORD DICTIONARY
tapetum, n. a light-reflecting part of the choroid membrane in the eyes of certain mammals, e.g. cats.
Etymology
LL f. L tapete carpet
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