The Collaborative International Dictionary of English v.0.48:

Cathedral \Ca*the"dral\, n. [LL. cathedralis (sc. ecclesia): cf.
   F. cath['e]drale. See Cathedra.]
   The principal church in a diocese, so called because in it
   the bishop has his official chair (Cathedra) or throne.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Cathedral \Ca*the"dral\, a. [LL. cathedralis: cf. F.
   cath['e]dral.]
   [1913 Webster]
   1. Pertaining to the head church of a diocese; as, a
      cathedral church; cathedral service.
      [1913 Webster]

   2. Emanating from the chair of office, as of a pope or
      bishop; official; authoritative.
      [1913 Webster]

            Now, what solemnity can be more required for the
            pope to make a cathedral determination of an
            article!                              --Jer. Taylor.
      [1913 Webster]

   3. Resembling the aisles of a cathedral; as, cathedral walks.
      --Pope.
      [1913 Webster]

WordNet (r) 3.0 (2006):

cathedral
    adj 1: relating to or containing or issuing from a bishop's
           office or throne; "a cathedral church"
    n 1: any large and important church
    2: the principal Christian church building of a bishop's diocese
       [syn: cathedral, duomo]

Moby Thesaurus II by Grady Ward, 1.0:

25 Moby Thesaurus words for "cathedral":
   accepted, approved, authentic, authoritative, basilica, bethel,
   cathedral church, church, church house, conventicle, duomo,
   ex cathedra, house of God, house of prayer, house of worship, kirk,
   magisterial, meetinghouse, minor basilica, mission, official,
   patriarchal basilica, place of worship, received, standard



The Jargon File (version 4.4.7, 29 Dec 2003):

cathedral
 n.,adj.

    [see bazaar for derivation] The ?classical? mode of software engineering
    long thought to be necessarily implied by Brooks's Law. Features small
    teams, tight project control, and long release intervals. This term came
    into use after analysis of the Linux experience suggested there might be
    something wrong (or at least incomplete) in the classical assumptions.