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1.                 From The Collaborative International Dictionary of English v.0.48:
                   
   
   
                   
                     
   Whilst \Whilst\, adv. [From Whiles; cf. Amongst.]
      While. [Archaic]
      [1913 Webster]
            Whilst the emperor lay at Antioch.       --Gibbon.
      [1913 Webster]
      The whilst, in the meantime; while. [Archaic.] --Shak.
         [1913 Webster]