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1.                 From The Collaborative International Dictionary of English v.0.48:
                   
   
   
                   
                     
   Gast \Gast\ (g[.a]st), v. t. [OE. gasten, g[=ae]sten to
      frighten, akin to Goth. usgaisjan. See Aghast, Ghastly,
      and cf. Gaze.]
      To make aghast; to frighten; to terrify. See Aghast. [Obs.]
      --Chaucer. Shak.
      [1913 Webster]