bungler

from WordNet (r) 3.0 (2006)

bungler
    n 1: someone who makes mistakes because of incompetence [syn:
         {bungler}, {blunderer}, {fumbler}, {bumbler}, {stumbler},
         {sad sack}, {botcher}, {butcher}, {fuckup}]

from The Collaborative International Dictionary of English v.0.48

Bungler \Bun"gler\, n.
   A clumsy, awkward workman; one who bungles.
   [1913 Webster]

         If to be a dunce or a bungler in any profession be
         shameful, how much more ignominious and infamous to a
         scholar to be such!                      --Barrow.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

41 Moby Thesaurus words for "bungler":
      blockhead, blunderbuss, blunderer, blunderhead, boor, botcher,
      bumbler, clod, clodhopper, clodknocker, clot, clown, disregarder,
      dodger, dolt, fumbler, gawk, goldbrick, goof-off, gowk, idler,
      ignorer, klutz, looby, lout, lubber, malingerer, neglecter,
      negligent, oaf, ox, procrastinator, shirker, slacker, slouch,
      sloven, slubberer, slut, trifler, waiter on Providence, yokel

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