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.
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            [Fish], sporting with quick glance,
            Show to the sun their waved coats dropt with gold.
                                                  --Milton.
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   2. To practice the diversions of the field or the turf; to be
      given to betting, as upon races.
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   3. To trifle. "He sports with his own life." --Tillotson.
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   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.
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   Syn: To play; frolic; game; wanton.
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