[1] : WordNet (r) 2.0

pinhead
     n 1: an ignorant or foolish person syn: dumbbell, dummy, dope,
           boob, booby
     2: the head of a pin
see also:
dumbbell dummy dope boob booby 

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

89 moby thesaurus words for "pinhead":
   addlebrain, addlehead, addlepate, beefhead, beetleheaded,
   blockhead, blockheaded, blubberhead, blunderhead, bonehead,
   bufflehead, cabbagehead, cap, capsheaf, caput, chowderhead,
   chucklehead, chuckleheaded, clodhead, clodpate, clodpoll, cluck,
   crest, crown, crumb, dense, dimwit, dolthead, doltish, dot, drop,
   droplet, dullhead, dumb cluck, dumbhead, dunderhead, dunderpate,
   fathead, fatheaded, featherweight, fleck, flyspeck, gnat, grain,
   head, heading, headpiece, iota, jolterhead, jot, jughead,
   knucklehead, lackwit, lunkhead, meathead, microbe, microorganism,
   midge, minim, minutia, minutiae, mite, mote, muddlehead, mushhead,
   muttonhead, nitwit, noodlehead, numskull, particle, peabrain,
   pinbrain, pinpoint, point, puddinghead, pumpkin head, puzzlehead,
   scrap, simp, snip, snippet, speck, stupidhead, thickhead,
   thickskull, tittle, topknot, tottyhead, vanishing point

Pinhead >> P Words
Pinhead, definition of term: Pinhead
pinhead_pag1.html