Boeotian,
asinine, beef-brained,
beef-witted,
blockish,
bovine,
chumpish,
cloddish,
cowish,
crass,
dense,
doltish,
dullard,
dumb,
duncical,
duncish,
fat,
gross,
ineducable,
lumpish,
oafish,
opaque,
sottish,
stupid,
thick,
unteachable,
wrongheaded