dam
The mother of a horse.
dead heat
Two or more horses finishing a race in a tie.
disqualification
Harness racing:Disqualified persons may not act as an official or start or drive a horse in a race. Disqualified horses shall not be allowed to start.
Thoroughbred racing: Change in order of finish by officials for an infraction of the rules.
draw
The process by which horses are selected to start in specific races and post positions for each race.
driver
A licensed person who drives a horse in a race.
drug
Any substance intended for use in the diagnosis, cure, mitigation, treatment or prevention of disease in humans or other animals.