thick-skulled

from WordNet (r) 3.0 (2006)

thick-skulled
    adj 1: (used informally) stupid [syn: {blockheaded},
           {boneheaded}, {duncical}, {duncish}, {fatheaded},
           {loggerheaded}, {thick}, {thickheaded}, {thick-skulled},
           {wooden-headed}]

from The Collaborative International Dictionary of English v.0.48

Thick-skulled \Thick"-skulled`\, a.
   Having a thick skull; hence, dull; heavy; stupid; slow to
   learn.
   [1913 Webster]

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