Person of extremely low intelligence or ability. The word Idiot started out in the early 20th century as a medical category for people with very severe intellectual disability and comes from the Greek word idiotes, which means “lacking skill”. It was originally used to categorize people with an IQ between 0 and 25. In this scale an “Imbecile” was a person with an IQ between 26 and 50, while a “Moron” had an IQ between 51 and 75.
In recent decades these words have come to be viewed as derogatory. On October 5, 2010, President Barack Obama signed Senate Bill 2781, known as “Rosa’s Law”, which changed the references in most Federal statutes that referred to “mental retardation” to “intellectual disability”.
“That idiot has failed his driver’s license for the fourth time!”.