(1):

(n.) A man in private station, as distinguished from one holding a public office.

(2):

(n.) An unlearned, ignorant, or simple person, as distinguished from the educated; an ignoramus.

(3):

(n.) A human being destitute of the ordinary intellectual powers, whether congenital, developmental, or accidental; commonly, a person without understanding from birth; a natural fool; a natural; an innocent.

(4):

(n.) A fool; a simpleton; - a term of reproach.