Young Eclipse was a Thoroughbred racehorse that won the 1781 Epsom Derby. He raced until he was six years old, winning seven races and retiring to stud in 1785. He was not a successful sire.

The Derby Stakes, also known as the Derby or the Epsom Derby, is a Group 1 flat horse race in England open to three-year-old colts and fillies. It is run at Epsom Downs Racecourse in Surrey on the first Saturday of June each year, over a distance of one mile, four furlongs and 10 yards, or about 1½ miles. It was first run in 1780.