It will be the epitaph on George Bush's gravestone.

Yes, you can use it. Its meaning is THICKHEADED, slow to understand, or stupid. I can't believe she cheated on him and didn't tell him for a whole month, she thought everything would be okay, shes sooo dense. Sorry to seem dense, but are there really Martians? Sorry for being dense, but what is a conehead? - Sorry for being dense. - Sorry to be dense. - Sorry to seem dense. All of the above have basically the same meaning. When the adjective "dense" is followed by a linking verb (to seem or to be, etc.) it expresses a state but no action.

Dense Definition: slow, stupid Synonyms: blockheaded, boorish, doltish, dull, dumb, fatheaded, ignorant, imbecilic, impassive, lethargic, numskulled, oafish, obtuse, phlegmatic, simple, slow-witted, sluggish, stolid, thick, torpid Antonyms: brainy, clever, intelligent, smart Check this useful site. http://thesaurus.com/browse/dense

dense means stupid. he's so dense, i have to tell him everything twice.