A person who is too stupid for words. A person that you wonder how and why they are still alive. A person so stupid that you know it's just a matter of time before they are killed by nothing more than their shear stupidity.
On 3 separate occasions I have seen people standing next to their cars unable to unlock their car door because the battery in the key fob had died and they didn't know what to do. On each occasion I took the keys from their hands and unlocked the door WITH THE KEYS! Man! Talk about WALKING-ROAD-KILL!