stride
Manner of going. Also, distance covered between successive imprints of the same hoof.
stud
1) Male horse used for breeding. 2) A breeding farm.
stud book
Registry and genealogical record of Thoroughbreds, maintained by the Jockey Club of the country in question. Use lower case when describing a generic stud book, all words, including “The,” are capitalized when describing “The American Stud Book.”
subscription
Fee paid by owner to nominate a horse for a stakes race or to maintain eligibility for a stakes race.
substitute race
Alternate race used to replace a regularly scheduled race that does not fill or is canceled.
suckling
A foal in its first year of life, while it is still nursing.
