oafish
blockish, Boeotian, boneheaded (slang) bovine, brutish, dense, dim, dim-witted (informal) doltish, dozy (Brit. informal) dull, dumb (informal) heavy, loutish, lubberly, lumbering, moronic, obtuse, slow on the uptake (informal) stupid, thick
Antonyms
acute, brainy (informal) bright, clever, intelligent, quick-witted, sharp, smart