The Collaborative International Dictionary of English v.0.48:

Authorized \Au"thor*ized\, a.
   1. Possessed of or endowed with authority; as, an authorized
      agent.
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   2. Sanctioned by authority.
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   The Authorized Version of the Bible is the English
      translation of the Bible published in 1611 under sanction
      of King James I. It was "appointed to be read in
      churches," and has been the accepted English Bible. The
      Revised Version was published in a complete form in 1855.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Authorize \Au"thor*ize\, v. t. [imp. & p. p. Authorized; p.
   pr. & vb. n. Authorizing.] [OE. autorize, F. autoriser, fr.
   LL. auctorizare, authorisare. See Author.]
   1. To clothe with authority, warrant, or legal power; to give
      a right to act; to empower; as, to authorize commissioners
      to settle a boundary.
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   2. To make legal; to give legal sanction to; to legalize; as,
      to authorize a marriage.
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   3. To establish by authority, as by usage or public opinion;
      to sanction; as, idioms authorized by usage.
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   4. To sanction or confirm by the authority of some one; to
      warrant; as, to authorize a report.
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            A woman's story at a winter's fire,
            Authorized by her grandam.            --Shak.
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   5. To justify; to furnish a ground for. --Locke.
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   To authorize one's self, to rely for authority. [Obs.]
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            Authorizing himself, for the most part, upon other
            histories.                            --Sir P.
                                                  Sidney.
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WordNet (r) 3.0 (2006):

authorized
    adj 1: endowed with authority [syn: authorized, authorised]
           [ant: unauthorised, unauthorized]
    2: sanctioned by established authority; "an authoritative
       communique"; "the authorized biography" [syn:
       authoritative, authorized, authorised]

Moby Thesaurus II by Grady Ward, 1.0:

75 Moby Thesaurus words for "authorized":
   absolute, accredited, actionable, applicable, appointed, ascendant,
   authoritarian, authoritative, autocratic, chartered,
   clothed with authority, commanding, commissioned, competent,
   consequential, considerable, constitutional, controlling,
   delegated, deputized, dominant, duly constituted, eminent,
   empowered, enfranchised, entitled, ex officio, franchised,
   governing, great, hegemonic, hegemonistic, imperative, important,
   influential, judicial, juridical, just, justiciable, kosher,
   lawful, lawmaking, leading, legal, legislative, legit, legitimate,
   licensed, licit, mighty, momentous, monocratic, official, patented,
   potent, powerful, preeminent, prestigious, privileged, prominent,
   puissant, ranking, rightful, ruling, sanctioned, senior, statutory,
   substantial, superior, supreme, totalitarian, valid, warranted,
   weighty, within the law