authoritynoun/ɔːˈθɒɹəti/

• 1

  Power or right to make or enforce rules, give orders, or impose obligation; or a position having such power or right.

  • I have the authority to penalise the staff in my department, but not the authority to sack them.
  • Vigilantes may have the power to nab criminals, but they lack the authority.
• 2

  Persons, regarded collectively, who occupy official positions of power; police or law enforcement.

  • Authorities say the suspect fled on foot.
  • The case was that of a murder. It had an element of mystery about it, however, which was puzzling the authorities. A turban and loincloth soaked in blood had been found; also a staff.
• 3

  A reliable, definitive source of information on a subject.

  • the world's foremost authority on orangutans
  • My cheap dictionary is not the authority on word derivations.
• 4

  Status as a trustworthy source of information, reputation for mastery or expertise; or claim to such status or reputation.

  • Due to being inadequate for the deductive method of reasoning, the argument from authority is considered a logical fallacy.
• 5

  Official permission; authorisation to act in some capacity on behalf of a ruling entity.

  • 'It seems to me,' remarked Mr Carrados, remembering something very similar not long before, 'that whatever anyone wants to do about Shakespeare, it is easy to find authority in his works for doing it.'
  • Authority to construct eight carriages, to test the new design in public service, had already been given; but of course complete working drawings had first to be prepared.
• 6

  A government-owned agency that runs a revenue-generating activity for public benefit.

  • New York Port Authority
  • Chicago Transit Authority