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1.                 From The Collaborative International Dictionary of English v.0.48:
                   
   
   
                   
                     
   Monas \Mo"nas\, n. [NL. See Monad.] (Zool.)
      A genus of minute flagellate Infusoria of which there are
      many species, both free and attached. See Illust. under
      Monad.
      [1913 Webster]