Uberon definition : 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.;
Uberon synonym : nictitans; third eyelid;
Uberon related term : haw;
Uberon Taxon note : The Calabar angwantibo (Arctocebus calabarensis, a lorisoid) is the only primate to
have a functioning nictitating membrane[Wikipedia:Calabar_angwantibo];
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.