[1] : 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
see also:
nonplused nonplussed nonplusing nonplussing 

[2] : WordNet (r) 2.0

nonplused
     adj : filled with bewilderment; "at a loss to understand those
           remarks"; "puzzled that she left without saying
           goodbye" syn: at a lossp, nonplussed, puzzled
see also:
at a lossp nonplussed puzzled 

Nonplused >> N Words
Nonplused, definition of term: Nonplused
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