n. pl. au·thor·i·ties

    1. The power to enforce laws, exact obedience, command, determine, or judge.
    2. One that is invested with this power, especially a government or body of government officials: land titles issued by the civil authority.
  1. Power assigned to another; authorization: Deputies were given authority to make arrests.
  2. A public agency or corporation with administrative powers in a specified field: a city transit authority.
    1. An accepted source of expert information or advice: a noted authority on birds; a reference book often cited as an authority.
    2. A quotation or citation from such a source: biblical authorities for a moral argument.
  3. Justification; grounds: On what authority do you make such a claim?
  4. A conclusive statement or decision that may be taken as a guide or precedent.
  5. Power to influence or persuade resulting from knowledge or experience: political observers who acquire authority with age.
  6. Confidence derived from experience or practice; firm self-assurance: played the sonata with authority.

[Middle English auctorite, from Old French autorite, from Latin auctrits, auctritt-, from auctor, creator. See author.]

Source: The American Heritage® Dictionary of the English Language, Fourth Edition
Copyright © 2000 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.