| half-brother, half-sister |
 | Horses out of the same dam but by different sires. Horses with the same sire and different dams are not considered half-siblings in Thoroughbred racing. |
| halter |
| Like a bridle, but lacking a bit. Used in handling horses around the stable and when they are not being ridden. (to) halter,Slang for claiming a horse. |
| hand |
| Four inches. A horse's height is measured in hands and inches from the top of the shoulder (withers) to the ground, e.g., 15.2 hands is 15 hands, 2 inches. Thoroughbreds typically range from 15 to 17 hands. |
| hand ride |
| Urging a horse with the hands and not using the whip. |
| handicap |
| 1) Race for which the track handicapper assigns the weights to be carried. 2) To make selections on the basis of past performances. |
| handily |
| 1) Working in the morning with maximum effort. Compare with, 2) A horse racing well within itself, with little exertion from the jockey. |
| handle |
| Amount of money wagered in the parimutuels on a race, a program, during a meeting or for a year. |
| hard (track) |
| A condition of a turf course where there is no resiliency to the surface. |
| hard boot |
| Denotes a well-traveled breeder whose boots are caked with mud and therefore hard. By extension, a breeder or trainer whose methods are characterized as old-fashioned. Generally used in the phrase, "Kentucky hard-boot." |
| harrow |
| Implement or unit with pulling teeth or tines used to rake and loosen the upper surface of a track. |
| head |
| A margin between horses. One horse leading another by the length of its head. |
| head of the stretch |
| Beginning of the straight run to the finish line. |
| heat |
| 1) A race in which more then one running is required to decide the winner. More common in harness racing. 2) A breeding term. See estrus. |
| heaves |
| Emphysema. See chronic obstructive pulmonary disease. |
| heavy (track) |
| Wettest possible condition of a turf course; not usually found in North America. |
| heel crack |
| A crack on the heel of the hoof. Also called a "sand crack." |
| helmet |
| A lightweight fiberglass cap worn by riders to prevent head injuries. It is required equipment that is not considered part of a jockey's riding weight. |
| hematoma |
| A blood-filled area resulting from injury. |
| high weight |
| Highest weight assigned or carried in a race. |
| hip |
| Joint located in the hindquarters, which is formed by the pelvis and the femur. |
| hock |
| A large joint just above the shin bone in the rear legs. Corresponds to the level of the knee of the front leg. |
| homebred |
| A horse bred by its owner. |
| hood |
| A (usually) nylon covering which goes over a horse's head to which blinkers or earmuffs are attached. |
| hoof |
| The foot of the horse. Consists of several parts that play an integral role in supporting the weight of the horse. See "Hoof" subsection of "Musculoskeletal System" in veterinary supplement for a more detailed explanation. For hoof injuries, see cracked hoof; heel crack; quarter crack; toe crack. |
| hopped |
| A horse that has been illegally stimulated. |
| horse |
| When reference is made to sex, a "horse" is an ungelded male five-years-old or older. |
| horsing |
| Behavior of a mare in heat (in season). See estrus. |
| hot walker |
| Person who walks horses to cool them out after workout or races. |
| hung |
| A horse that does not advance its position in a race when called upon by its jockey. |
| hyaluronic acid |
| A normal component of joint fluid. Also can be a man-made intra-articular medication used to relieve joint inflammation. |
