The Collaborative International Dictionary of English v.0.48:

Blazer \Blaz"er\, n.
   One who spreads reports or blazes matters abroad. "Blazers of
   crime." --Spenser.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Blazer \Blaz"er\, n.
   1. Anything that blazes or glows, as with heat or flame.
      [Webster 1913 Suppl.]

   2. A light jacket, usually of wool or silk and of a bright
      color, for wear at tennis, cricket, or other sport.
      [Webster 1913 Suppl.]

   3. The dish used when cooking directly over the flame of a
      chafing-dish lamp, or the coals of a brasier.
      [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

blazer
    n 1: lightweight single-breasted jacket; often striped in the
         colors of a club or school [syn: blazer, sport jacket,
         sport coat, sports jacket, sports coat]

Moby Thesaurus II by Grady Ward, 1.0:

45 Moby Thesaurus words for "blazer":
   Eton jacket, Mao jacket, blouse, body coat, bolero, bomber jacket,
   capuchin, car coat, chaqueta, chesterfield, claw hammer,
   claw-hammer coat, cutaway coat, dinner jacket, doublet, dress coat,
   duffel, fingertip coat, fitted coat, frock, frock coat, jerkin,
   jumper, jupe, loden coat, mackinaw, mess jacket, midicoat,
   monkey jacket, parka, pea jacket, reefer, sack, san benito,
   ski jacket, sleeve waistcoat, smoking jacket, spiketail coat,
   swallowtail, tabard, tail coat, tails, watch coat, windbreaker,
   woolly