nincompoop

from WordNet (r) 3.0 (2006)

nincompoop
    n 1: a stupid foolish person [syn: {nincompoop}, {poop},
         {ninny}]

from The Collaborative International Dictionary of English v.0.48

nincompoop \nin"com*poop\, n. [A corruption of non compos.]
   A fool; a silly or stupid person. [Law]
   [1913 Webster]

         An old ninnyhammer, a dotard, a nincompoop, is the best
         language she can afford me.              --Addison.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

34 Moby Thesaurus words for "nincompoop":
      Boeotian, ass, block, clod, dimwit, dolt, donkey, dope, dullard,
      dumb cluck, dumbbell, dummy, dunce, gowk, idiot, imbecile, jackass,
      jerk, jobbernowl, lackwit, lamebrain, lightweight, looby, loon,
      niais, ninny, ninnyhammer, nitwit, noddy, put, stupid, thickwit,
      tomfool, witling

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