The Collaborative International Dictionary of English v.0.48:

Stanza \Stan"za\ (st[a^]n"z[.a]), n.; pl. Stanzas (-z[.a]z).
   [It. stanza a room, habitation, a stanza, i. e., a stop, fr.
   L. stans, p. pr. of stare to stand. See Stand, and cf.
   Estancia, Stance, Stanchion.]
   1. A number of lines or verses forming a division of a song
      or poem, and agreeing in meter, rhyme, number of lines,
      etc., with other divisions; a part of a poem, ordinarily
      containing every variation of measure in that poem; a
      combination or arrangement of lines usually recurring,
      whether like or unlike, in measure.
      [1913 Webster]

            Horace confines himself strictly to one sort of
            verse, or stanza, in every ode.       --Dryden.
      [1913 Webster]

   2. (Arch.) An apartment or division in a building; a room or
      chamber.
      [1913 Webster]

WordNet (r) 3.0 (2006):

stanza
    n 1: a fixed number of lines of verse forming a unit of a poem

Moby Thesaurus II by Grady Ward, 1.0:

68 Moby Thesaurus words for "stanza":
   Spenserian stanza, anacrusis, antistrophe, bass passage, book,
   bourdon, bridge, burden, cadence, canto, chorus, coda, couplet,
   development, distich, division, envoi, epode, exposition, figure,
   folderol, harmonic close, heptastich, hexastich, interlude,
   intermezzo, introductory phrase, line, measure, monostich,
   movement, musical phrase, musical sentence, octastich, octave,
   octet, ornament, ottava rima, part, passage, pentastich, period,
   phrase, quatrain, refrain, resolution, response, rhyme royal,
   ritornello, section, septet, sestet, sextet, statement, stave,
   strain, strophe, syllable, tailpiece, tercet, terza rima,
   tetrastich, triplet, tristich, tutti, tutti passage, variation,
   verse