Explore: Eyelid Conditioning.

An eyelid (/ˈaɪ.lɪd/ EYE-lid) is a thin fold of skin that covers and protects an eye. The levator palpebrae superioris muscle retracts the eyelid, exposing

membrane (from Latin nictare, to blink) is a transparent or translucent third eyelid present in some animals that can be drawn across the eye from the medial

1942. There, Spence established an eyelid-conditioning lab to study the influence of motivation on classical conditioning, and contributed to Clark Hull's

or falling of the upper eyelid. This condition is sometimes called "lazy eye", but that term normally refers to the condition amblyopia. If severe enough

granulated eyelids, is one of the most common ocular conditions characterized by inflammation, scaling, reddening, and crusting of the eyelid. This condition may

Blepharoplasty, from Ancient Greek βλέφαρον (blépharon), meaning "eyelid", and πλαστός (plastós), meaning "moulded", is the plastic surgery operation for

an oil gland in the eyelid. This results in a red tender bump at the edge of the eyelid. The outside or the inside of the eyelid can be affected. The

Eyelid dermatitis is commonly related to atopic dermatitis or allergic contact dermatitis. Volatile substances, tosylamide/formaldehyde resin, epoxy hardeners

Dermatochalasis is a medical condition, defined as an excess of skin in the upper or lower eyelid, also known as "baggy eyes." It may be either an acquired

the Greek: βλέφαρον / blepharon, eyelid, and σπασμός / spasmos, spasm, an uncontrolled muscle contraction. The condition should be distinguished from the