Dumbiful

The act of being really dumb to the point beyond belief and to the point where you want to cry.

A derogatory slang term for a specific type of metal head that is extremely elitist, is rarely seen in places other than the internet, listens to doom metal, plays Dungeons and Dragons, World of Warcraft or engages in some other type of nerdy activity. A dumbis is usually fat and will dress in cargo shorts, skate shoes, and an Isis shirt. Dumbi rarely have long hair like other metal heads, instead opting for a long neck beard or slightly "shaggy" hair.

Someone, usually a friend, who does something unbelievably betraying or idiotic. Strong way of saying, "dummy."

Common misspelling of the word dummy, almost always used by the people who can easily be described by the word itself. Just because dumb has a "b" at the end, does not mean dummy has to. Also, dummy does not rhyme with Gumby.

a dumbass and a newbie to certain things

a slang term for a specific type of metal head, that is usually fat, nerdy and wears cargo shorts. Dumbi generally listen to sludge metal, and are very pretentious. They'll talk your ear off about Dungeons and Dragons too.

It must be pronounced with a hard "B"

Its definition is unspoken.