idiot

An idiot, in modern use, is a stupid or foolish person.
"Idiot" was formerly a technical term in legal and psychiatric contexts for some kinds of profound intellectual disability where the mental age is two years or less, and the person cannot guard themself against common physical dangers. The term was gradually replaced by "profound mental retardation", which has since been replaced by other terms. Along with terms like moron, imbecile, retard and cretin, its use to describe people with mental disabilities is considered archaic and offensive. Moral idiocy refers to a moral disability.

View More On Wikipedia.org