"Sport": "In botany, a sport or bud sport is a part of a plant (normally a woody plant, but sometimes in herbs as well) that shows morphological differences from the rest of the plant. Sports may differ by foliage shape or color, flowers, or branch structure.

Sports with desirable characteristics are often propagated vegetatively to form new cultivars that retain the characteristics of the new morphology. Such selections are often prone to "reversion", meaning that part or all of the plant reverts to its original form. An example of a bud sport is the nectarine, which developed from a bud sport from a peach." http://en.wikipedia.org/wiki/Sport_%28botany%29