The Collaborative International Dictionary of English v.0.48:

Nictation \Nic*ta"tion\, n. [L. nictatio; cf. F. nictation.]
   The act of winking; nictitation.
   [1913 Webster]

WordNet (r) 3.0 (2006):

nictation
    n 1: a reflex that closes and opens the eyes rapidly [syn:
         blink, eye blink, blinking, wink, winking,
         nictitation, nictation]