Nictitating Membrane
Synonyms
Eyelid, Third
Eyelids, Third
Membrane, Nictitating
Membranes, Nictitating
Nictitating Membranes
Third Eyelid
Third Eyelids
A fold of the mucous membrane of the CONJUNCTIVA in many animals. At rest, it is hidden in the medial canthus. It can extend to cover part or all of the cornea to help clean the CORNEA.