A person who is stupid and entirely tedious at the same time. Many times they are oblivious to their own mental incapacity.

"allow it" means to just leave something alone, or don't worry about it. People in West London say this quite often.

A person who isn’t very bright but is very nice and weird

(N.) A stupid person; a dunce.

This is a real word. It has no place in Urban-dictionary.

Dolts are not necessarily stupid people, but engage in stupid actions or make stupid comments. Others around them would define their actions as dumb, spaced-out, or uneducated. Dolts often "speak to soon" as their stupid actions are often preventable.

One who is incapable of rational thought, an organized logic, or reasonable social interaction. Know to those around them as an idiot or stupid. Usually, a dolt will not have the capacity to understand just how stupid they really are and will likely blame others for their failures and inabilities.

One who lacks knowledge of any and all things around him/her. An individual who has a severe mental retardation, and paints their (racing car)interior red and yellow.