Definition of Eyelid

Eyelid: The lid or cover of the eye, a movable fold of skin and muscle that can be closed over the eyeball or opened at will. Each eye has an upper and a lower lid. Also known as a palpebra.

Source: MedTerms™ Medical Dictionary
http://www.medterms.com/script/main/art.asp?articlekey=22452
Last Editorial Review: 3/19/2012