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1.                 From The Collaborative International Dictionary of English v.0.48:
                   
   
   
                   
                     
   Thrustle \Thrus"tle\, n. (Zool.)
      The throstle, or song thrust. [Obs. or Prov. Eng.]
      [1913 Webster]
            When he heard the thrustel sing.         --Chaucer.
      [1913 Webster]