third eyelid


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third eyelid

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

third eyelid

n
(Zoology) another name for nictitating membrane
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

nic′titating mem′brane


n.
a thin membrane, present in many animals, that can be drawn across the eyeball for protection.
[1705–15]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.third eyelid - a protective fold of skin in the eyes of reptiles and birds and some mammalsthird eyelid - 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
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
The problem was called a third eyelid gland prolapse.
Dogs in the field are exposed to myriad foreign bodies that can lodge in the eye, or beneath the third eyelid. Close inspection and flushing of the eyes with an eye wash after each hunt is important.
AYOU could be seeing your dog's third eyelid or swollen conjunctiva (the pink soft tissue that surrounds the eye), rather than your dog's eye rolling up.
The most common areas of the tumors are the limbus (junction of the cornea and the sclera), the third eyelid, and on the upper and lower eyelid margins.
They all have a nictitating membrane -- that creepy third eyelid.
Then use your fingers to peel back the eyelids and take a look at both top and bottom, and in the front corner where the third eyelid is located, to see if you can find anything caught in there.
Birds have upper and lower eyelids and a nictitating membrane (or third eyelid).
The third eyelid is an extra protective eyelid in the dog and is also covered by conjunctiva.
Notice the tearing and matting around the eye from irritation, as well as the prominence of the third eyelid, which has elevated in order to protect the cornea.
Primary Lacrimal gland adenocarsinoma of the third eyelid in a horse.
Foreign bodies - Something could be in the eye, possibly hiding under the third eyelid and could be a source of chronic irritation.