by pure definition of the word alone, greyhounds and horses are not athletes. An athlete refers to a Person. Race car drivers are not athletes. Nascar is a sporting event, not an athletic contest.
ath·lete ( P ) Pronunciation Key (thlt)
n.
A person possessing the natural or acquired traits, such as strength, agility, and endurance, that are necessary for physical exercise or sports, especially those performed in competitive contexts.
sport ( P ) Pronunciation Key (spôrt, sprt)
n.
Physical activity that is governed by a set of rules or customs and often engaged in competitively.
A particular form of this activity.
An activity involving physical exertion and skill that is governed by a set of rules or customs and often undertaken competitively.
An active pastime; recreation.