Whisker was a Thoroughbred racehorse that won the 1815 Epsom Derby and was a full-brother of the 1810 winner Whalebone. Whisker raced until he was a six-year-old, but did not race in 1817. Whisker was retired to stud in 1819, where he became a successful and influential sire. The offspring of Whisker and Whalebone continued the sire-line of Eclipse into the 20th century.