The Collaborative International Dictionary of English v.0.48:

Sporting \Sport"ing\, a.
   Of, pertaining to, or engaging in, sport or sports;
   exhibiting the character or conduct of one who, or that
   which, sports.
   [1913 Webster]

   Sporting book, a book containing a record of bets, gambling
      operations, and the like. --C. Kingsley.

   Sporting house, a house frequented by sportsmen, gamblers,
      and the like.

   Sporting man, one who practices field sports; also, a horse
      racer, a pugilist, a gambler, or the like.

   Sporting plant (Bot.), a plant in which a single bud or
      offset suddenly assumes a new, and sometimes very
      different, character from that of the rest of the plant.
      --Darwin.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Sport \Sport\, v. i. [imp. & p. p. Sported; p. pr. & vb. n.
   Sporting.]
   1. To play; to frolic; to wanton.
      [1913 Webster]

            [Fish], sporting with quick glance,
            Show to the sun their waved coats dropt with gold.
                                                  --Milton.
      [1913 Webster]

   2. To practice the diversions of the field or the turf; to be
      given to betting, as upon races.
      [1913 Webster]

   3. To trifle. "He sports with his own life." --Tillotson.
      [1913 Webster]

   4. (Bot. & Zool.) To assume suddenly a new and different
      character from the rest of the plant or from the type of
      the species; -- said of a bud, shoot, plant, or animal.
      See Sport, n., 6. --Darwin.
      [1913 Webster]

   Syn: To play; frolic; game; wanton.
        [1913 Webster]

WordNet (r) 3.0 (2006):

sporting
    adj 1: exhibiting or calling for sportsmanship or fair play; "a
           clean fight"; "a sporting solution of the disagreement";
           "sportsmanlike conduct" [syn: clean, sporting,
           sporty, sportsmanlike]
    2: relating to or used in sports; "sporting events"; "sporting
       equipment"
    3: involving risk or willingness to take a risk; "a sporting
       chance"; "sporting blood"
    4: preoccupied with the pursuit of pleasure and especially games
       of chance; "led a dissipated life"; "a betting man"; "a card-
       playing son of a bitch"; "a gambling fool"; "sporting gents
       and their ladies" [syn: dissipated, betting, card-
       playing, sporting]

Moby Thesaurus II by Grady Ward, 1.0:

41 Moby Thesaurus words for "sporting":
   acrobatic, agonistic, athletic, betting, cardsharping,
   casting lots, chase, chevy, chivy, coursing, cynegetics,
   fair-minded, falconry, fox hunting, gambling, gaming, gunning,
   gymnastic, hawking, hazarding, hunt, hunting, palaestral, play,
   playing, risking, shikar, shooting, sortition, speculation, sport,
   sports, sportsmanlike, sportsmanly, square-dealing,
   square-shooting, staking, stalking, still hunt, venery, wagering