The Whippet (also English Whippet or Snap Dog) is a dog breed of medium size. They are a sighthound breed that originated in England, where they descended from Greyhounds. Whippets today still strongly resemble a smaller Greyhound. They are a sighthound breed that originated in England, where they descended from Greyhounds. Part of the Hound group, Whippets have relatively few health problems other than arrhythmia. Whippets also participate in dog sports such as lure coursing, agility, and flyball. The name is derived from an early 17th-century word, now obsolete, meaning 'to move briskly'. There has been continuity in describing Greyhound-types of different sizes: large, medium and small, as recorded in hunting manuals and works on natural history from the Middle Ages. Edward of Norwich, 2nd Duke of York confirmed in his early 15th century translation and additions to the original late 14th century French Livre de chasse the advantage of maintaining the great, the middle, and the small size of greyhound for different sorts of game.