[1] : The Collaborative International Dictionary of English v.0.48

half-wit \half"-wit`\ -wi^t`, n.
   a foolish person; a dolt; a blockhead; a dunce. --dryden.
   1913 webster

[2] : WordNet (r) 2.0

half-wit
     n 1: a person of subnormal intelligence syn: idiot, imbecile,
           cretin, moron, changeling, retard
     2: a stupid incompetent person syn: dimwit, nitwit, doofus
see also:
idiot imbecile cretin moron changeling retard 
dimwit nitwit doofus 

[3] : Moby Thesaurus II by Grady Ward, 1.0

18 moby thesaurus words for "halfwit":
   ass, birdbrain, dolt, dullard, dunce, dunderhead, dunderpate, fool,
   idiot, imbecile, moron, nincompoop, ninny, nit, nitwit, numskull,
   simpleton, twit

Halfwit >> H Words
Halfwit, definition of term: Halfwit
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