The third eyelid, or nictitating membrane. See Nictitating membrane, under Nictitate.
The third eyelid at the inner corner of a dog's eye. The haw lubricates and protects the eye. It can be seen in Basset Hounds, Bloodhounds, St. Bernards and other droopy-eyed dogs, but its barely noticable in most breeds.
A transparent, third eyelid at the inner side of the eye that keeps the eye clean and moist.
Exposed nictitating membrane (third eyelid), especially if unpigmented.
the nictitating membrane of a horse
non-veterinary term for the third eyelid
Protrusion of the third eyelid (thin membrane that moves across the eye when the upper and lower eyelids are closed), may be visible when a cat is sick
Nictitating membrane. Third or inner eyelid.
A third eyelid or membrane in the inside corner of the eye.
A nictitating membrane, especially of a domesticated animal.
the third eyelid: membrane on the inner corner of the eye, seen in wet faced breeds