Nic'ti·tate intransitive verb [ See Nictate .] To wink; to nictate. Nictitating membrane (Anat.) , a thin membrane, found in many animals at the inner angle, or beneath the lower lid, of the eye, and capable of being drawn across the eyeball; the third eyelid; the haw. Found on http://www.encyclo.co.uk/webster/N/20
Nictitate: To wink. Nictitating spasm is spasm of the eyelid with continuous winking. 'Nictitate' and the older verb 'nictate' both come from the Latin word for winking, 'nictare.' Found on http://www.medterms.com/script/main/art.asp?articlekey=10145