Authority
Part of speech: noun
Definition: The power to enforce rules or give orders. Persons in command; specifically, government. A person accepted as a source of reliable information on a subject.
Example sentence: Destiny: A tyrant's authority for crime and a fool's excuse for failure.
Authorization
Part of speech: noun
Definition: Permission.An act of authorizing.(A document giving) formal sanction, permission or warrant.Permission, possibly limited, to spend funds a specific budgetary purpose.The power or right to give orders.The permission to use a specific resource; access control.
Example sentence: I have said, with respect to authorization bills, that I do not want the Congress or the country to commit fiscal suicide on the installment plan.