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1.                 From The Collaborative International Dictionary of English v.0.48:
                   
   
   
                   
                     
   Flop \Flop\ (fl[o^]p), v. t. [imp. & p. p. Flopped (fl[o^]pt);
      p. pr. & vb. n. Flopping.] [A variant of flap.]
      1. To clap or strike, as a bird its wings, a fish its tail,
         etc.; to flap.
         [1913 Webster]
      2. To turn suddenly, as something broad and flat. [Colloq.]
         --Fielding.
         [1913 Webster]