Source : Webster's Revised Unabridged Dictionary (1913)

Nictitation \Nic`ti*ta"tion\, n.
   The act of winking.

Source : WordNet®

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