tapetum
Americannoun
plural
tapeta-
Botany. a layer of cells often investing the archespore in a developing sporangium and absorbed as the spores mature.
-
Anatomy, Zoology. any of certain membranous layers or layered coverings, as in the choroid of the eyes of certain animals.
noun
-
a layer of nutritive cells in the sporangia of ferns and anthers of flowering plants that surrounds developing spore cells
-
-
a membranous reflecting layer of cells in the choroid of the eye of nocturnal vertebrates
-
a similar structure in the eyes of certain nocturnal insects
-
-
anatomy a covering layer of cells behind the retina of the eye
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
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
But the blue tapetum also lets up to 60% of ultraviolet light pass through to the eye's color sensors.
From Science Daily • Dec. 15, 2023
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 • Oct. 4, 2023
An inner layer of cells, known as the tapetum, provides nutrition to the developing microspores and contributes key components to the pollen wall.
From Textbooks • Jan. 1, 2015
There is green “eye shine” from the tapetum lucidum, and a more pronounced superciliary arch.
From Forbes • Jun. 7, 2013
Iris tapetum: the pigment layer of the compound eye just below the crystalline cone.
From Explanation of Terms Used in Entomology by Smith, John. B.
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.