Cretin
Part of speech: noun
Definition: A person who fails to develop mentally and physically due to a congenital deficiency of thyroid hormones. An idiot.
Imbecile
Part of speech: noun
Definition: A person with limited mental capacity who can perform tasks and think only like a young child, in medical circles meaning a person who lacks the capacity to develop beyond the mental age of a normal five to seven-year-old child (not commonly used today)A fool, an idiot.
Example sentence: How hard it is to make your thoughts look anything but imbecile fools when you paint them with ink on paper.