tapetum

American  

[tuh-pee-tuhm] / təˈpi təm /

noun

plural

tapeta

1. Botany. a layer of cells often investing the archespore in a developing sporangium and absorbed as the spores mature.

2. Anatomy, Zoology. any of certain membranous layers or layered coverings, as in the choroid of the eyes of certain animals.

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tapetum British  

/ təˈpiːtəm /

noun

1. a layer of nutritive cells in the sporangia of ferns and anthers of flowering plants that surrounds developing spore cells

2. 1. a membranous reflecting layer of cells in the choroid of the eye of nocturnal vertebrates

   2. a similar structure in the eyes of certain nocturnal insects

3. anatomy a covering layer of cells behind the retina of the eye

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Other Word Forms

• tapetal adjective

Etymology

Origin of tapetum

1705–15; < New Latin, special use of Medieval Latin tapētum coverlet ( Latin, only plural) < Greek tapēt- (stem of tápēs ) carpet, rug

Example Sentences

The backs of a cat’s eyes have a layer called the tapetum lucidum, which reflects unabsorbed light back into the retinas, an adaptation to help the cat see in dim light, and causes eye shine, the glow that can be seen when light shines on them in the dark.

From National Geographic

Their tapetum -- the light-enhancing membrane that gives many animals "shiny" eyes -- transitions in winter from the golden color most animals have to a vivid blue that is thought to amplify the low light of polar winter.

From Science Daily

But the blue tapetum also lets up to 60% of ultraviolet light pass through to the eye's color sensors.

From Science Daily

They even have a unique structure in their eyes called the tapetum lucidum, a mirrorlike membrane that allows them to see in six times less light than humans can.

From Scientific American

The tapetum, which some other animals, such as cats and cattle, also possess, sits behind the retina and reflects light back onto it, giving the receptors a second chance to gather more visual detail.

From Scientific American