nictitating membrane


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nic·ti·tat·ing membrane

 (nĭk′tĭ-tā′tĭng)
n.
A transparent inner eyelid in many vertebrates that closes to protect and moisten the eye. Also called third eyelid.

nictitating membrane

(ˈnɪktɪˌteɪtɪŋ)
n
(Zoology) (in reptiles, birds, and some mammals) a thin fold of skin beneath the eyelid that can be drawn across the eye. Also called: third eyelid or haw

nic′titating mem′brane


n.
a thin membrane, present in many animals, that can be drawn across the eyeball for protection.
[1705–15]

nic·ti·tat·ing membrane

(nĭk′tĭ-tā′tĭng)
A transparent inner eyelid in birds, reptiles, amphibians, and some mammals that protects and moistens the eye without blocking vision.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.nictitating membrane - a protective fold of skin in the eyes of reptiles and birds and some mammalsnictitating membrane - a protective fold of skin in the eyes of reptiles and birds and some mammals
eye, oculus, optic - the organ of sight
protective fold - a flap of tissue that protects what it covers
haw - the nictitating membrane of a horse
References in classic literature ?
In South America, a burrowing rodent, the tuco-tuco, or Ctenomys, is even more subterranean in its habits than the mole; and I was assured by a Spaniard, who had often caught them, that they were frequently blind; one which I kept alive was certainly in this condition, the cause, as appeared on dissection, having been inflammation of the nictitating membrane.
Corneal sensitivity was considered present if the bird blinked its eyelids or flashed the nictitating membrane when the cotton wisp was applied; it was considered absent if no such response was observed, and diminished if the response was less robust than in cohort birds.
The plica semilunaris is thought to be the remains of a nictitating membrane or third eyelid (from the Latin nictare, meaning blink).
The nictitating membrane is a transparent or translucent additional eyelid that is present in some animals.
Lung, nasal turbinate, nasal septum, larynx, trachea, bronchus, tracheobronchial lymph node, nictitating membrane, tonsil, heart, liver, spleen, kidney, pancreas, duodenum, jejunum, colon, adrenal gland, brain, and olfactory bulb samples were obtained, were fixed in formalin, and processed to obtain sections for staining with hematoxylin and eosin.
It involves snipping a tiny piece of lymphoid tissue from the animal's nictitating membrane, or third eyelid, staining it with antibodies, and examining it under a microscope.