The Collaborative International Dictionary of English v.0.48:

dolt \dolt\ (d[=o]lt; 110), n. [OE. dulte, prop. p. p. of dullen
   to dull. See Dull.]
   A heavy, stupid fellow; a blockhead; a numskull; an
   ignoramus; a dunce; a dullard.
   [1913 Webster]

         This Puck seems but a dreaming dolt.     --Drayton.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

dolt \dolt\, v. i.
   To behave foolishly. [Obs.]
   [1913 Webster]

WordNet (r) 3.0 (2006):

dolt
    n 1: a person who is not very bright; "The economy, stupid!"
         [syn: stupid, stupid person, stupe, dullard,
         dolt, pudding head, pudden-head, poor fish,
         pillock]

Moby Thesaurus II by Grady Ward, 1.0:

76 Moby Thesaurus words for "dolt":
   Boeotian, ass, birdbrain, block, blockhead, blunderer, blunderhead,
   bonehead, boob, booby, boor, botcher, bumbler, bungler,
   chucklehead, chump, clod, clodhopper, clodknocker, clot, clown,
   dimwit, ding-a-ling, dingbat, dolthead, donkey, dope, dullard,
   dumb cluck, dumbbell, dummy, dunce, dunderhead, dunderpate,
   fathead, flake, fool, fumbler, gawk, goon, gowk, idiot, ignoramus,
   imbecile, jerk, jobbernowl, klutz, lackwit, lamebrain, lightweight,
   looby, loon, lout, lubber, lunkhead, moron, muggins, niais,
   nincompoop, ninny, ninnyhammer, nitwit, noddy, numskull, oaf, ox,
   pinhead, put, simpleton, slouch, slubberer, stupid, thickwit, twit,
   witling, yokel