The Collaborative International Dictionary of English v.0.48:

Tamer \Tam"er\, n.
   One who tames or subdues.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Tame \Tame\, a. [Compar. Tamer; superl. Tamest.] [AS. tam;
   akin to D. tam, G. zahm, OHG. zam, Dan. & Sw. tam, Icel.
   tamr, L. domare to tame, Gr. ?, Skr. dam to be tame, to tame,
   and perhaps to E. beteem. [root]61. Cf. Adamant, Diamond,
   Dame, Daunt, Indomitable.]
   1. Reduced from a state of native wildness and shyness;
      accustomed to man; domesticated; domestic; as, a tame
      deer, a tame bird.
      [1913 Webster]

   2. Crushed; subdued; depressed; spiritless.
      [1913 Webster]

            Tame slaves of the laborious plow.    --Roscommon.
      [1913 Webster]

   3. Deficient in spirit or animation; spiritless; dull; flat;
      insipid; as, a tame poem; tame scenery.
      [1913 Webster]

   Syn: Gentle; mild; meek. See Gentle.
        [1913 Webster]

WordNet (r) 3.0 (2006):

tamer
    n 1: an animal trainer who tames wild animals

Moby Thesaurus II by Grady Ward, 1.0:

26 Moby Thesaurus words for "tamer":
   breaker, breeder, broncobuster, buckaroo, cattleman, cow keeper,
   cowman, dairy farmer, dairyman, equerry, farrier, grazier, groom,
   horseshoer, hostler, rancher, ranchero, ranchman, sheepman,
   stableboy, stableman, stock raiser, stockbreeder, stockkeeper,
   stockman, trainer