Penelope (1798–1824) was a British Thoroughbred racehorse. She won sixteen of her twenty-four races, including two Oatlands Stakes, the Jockey-Club Plate and she beat Oaks and Derby winner Eleanor. She was bred and owned by Augustus FitzRoy, 3rd Duke of Grafton. After retiring from racing she became an influential broodmare, foaling Derby winners Whalebone and Whisker and 1000 Guineas winner Whizgig.

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.