headshake

from WordNet (r) 3.0 (2006)

headshake
    n 1: the act of turning your head left and right to signify
         denial or disbelief or bemusement; "I could tell from their
         headshakes that they didn't believe me" [syn: {headshake},
         {headshaking}]

from The Collaborative International Dictionary of English v.0.48

Headshake \Head`shake`\ (-sh[=a]k`), n.
   A significant shake of the head, commonly as a signal of
   denial. --Shak.
   [1913 Webster]

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