Greyhounds are a breed of dog used by European nobility for hunting.

The breed's origin is romantically reputed to be connected to Ancient Egypt, where depictions of smooth-coated sighthound types have been found which are typical of Saluki (Persian greyhound) or Sloughi (tombs at Beni Hassan c. 2000 BCE). However, analyses of DNA reported in 2004 suggest that the Greyhound is not closely related to these breeds, but is a close relative to herding dogs. Historical literature on the first sighthound in Europe (Arrian), the vertragus, the probable antecedent of the Greyhound, suggests that the origin is with the ancient Celts from Eastern Europe or Eurasia.

Greyhound-type dogs of small, medium, and large size, would appear to have been bred across Europe since that time. All modern, pure-bred pedigree Greyhounds are derived from the Greyhound stock recorded and registered, firstly in the private 18th century, then public 19th century studbooks, which ultimately were registered with coursing, racing, and kennel club authorities of the United Kingdom.

Historically, these sighthounds were used primarily for hunting in the open where their keen eyesight is valuable. It is believed that they (or at least similarly named dogs) were introduced to the area now known as the United Kingdom in the 5th and 6th century BCE from Celtic mainland Europe although the Picts and other peoples of the northern area now known as Scotland were believed to have had large hounds similar to that of the deerhound before the 6th century BCE.

The name “Greyhound” is generally believed to come from the Old English grighund. “Hund” is the antecedent of the modern “hound”, but the meaning of “grig” is undetermined, other than in reference to dogs in Old English and Old Norse. Its origin does not appear to have any common root with the modern word “grey” for color, and indeed the Greyhound is seen with a wide variety of coat colors. The lighter colors, patch-like markings and white appeared in the breed that was once ordinarily grey in color. The Greyhound is the only dog mentioned by name in the Bible; many versions, including the King James version, name the Greyhound as one of the “four things stately” in the Proverbs.