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1.                 From The Collaborative International Dictionary of English v.0.48:
                   
   
   
                   
                     
   Taconic \Ta*con"ic\, a. (Geol.)
      Designating, or pertaining to, the series of rocks forming
      the Taconic mountains in Western New England. They were once
      supposed to be older than the Cambrian, but later proved to
      belong to the Lower Silurian and Cambrian.
      [1913 Webster]