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1.                 From The Collaborative International Dictionary of English v.0.48:
                   
   
   
                   
                     
   Avast \A*vast"\ ([.a]*v[.a]st"), interj. [Corrupted from D. houd
      vast hold fast. See Hold, v. t., and Fast, a.] (Naut.)
      Cease; stop; stay. "Avast heaving." --Totten.
      [1913 Webster]