DuckCorp Dico

Found 2 definitions

1.                 From The Collaborative International Dictionary of English v.0.48:
                   
   
   
                   
                     
   Nonplus \Non"plus`\, v. t. [imp. & p. p. Nonplusedor
      Nonplussed; p. pr. & vb. n. Nonplusing or Nonplussing.]
      To puzzle; to confound; to perplex; to cause to stop by
      embarrassment.
      [1913 Webster]
            He has been nonplused by Mr. Dry's desiring him to tell
            what it was that he endeavored to prove. --Spectator.
      [1913 Webster]
   
                   
                 

2.                 From The Collaborative International Dictionary of English v.0.48:
                   
   
   
                   
                     
   Nonplus \Non"plus\, n. [L. non not + plus more, further. See
      Plural.]
      A state or condition which baffles reason or confounds
      judgment; insuperable difficulty; inability to proceed or
      decide; puzzle; quandary.
      [1913 Webster]
            Both of them are a perfect nonplus and baffle to all
            human understanding.                     --South.
      [1913 Webster]