Definition of authority
1a : power to influence or command thought, opinion, or behavior the president's authority
b : freedom granted by one in authority : right Who gave you the authority to do as you wish?
2a : persons in command specifically : government the local authorities of each state
b : a governmental agency or corporation to administer a revenue-producing public enterprise the transit authority the city's housing authority
b : convincing force lent authority to the performance
4a(1) : a citation (as from a book or file) used in defense or support
(2) : the source from which the citation is drawn He quoted extensively from the Bible, his sole authority.
b(1) : a conclusive statement or set of statements (such as an official decision of a court)
(2) : a decision taken as a precedent
(3) : testimony
c : an individual cited or appealed to as an expert The prosecutor called the psychiatrist as an authority.
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