Spendthrift was a successful American Thoroughbred racehorse and an outstanding sire.

In the United States, the Triple Crown of Thoroughbred Racing, commonly known as the Triple Crown, is a series of horse races for three-year-old Thoroughbreds, consisting of the Kentucky Derby, Preakness Stakes, and Belmont Stakes. The three races were inaugurated in different years, the last being the Kentucky Derby in 1875. The Triple Crown Trophy, commissioned in 1950 but awarded to all previous winners as well as those after 1950, is awarded to a horse who wins all three races and is thereafter designated as a Triple Crown winner. The races are traditionally run in May and early June of each year, although global events have resulted in schedule adjustments, such as in 1945 and 2020.