Herd (a word common to Teutonic languages; the O. Eng. form was heord; cf. Ger. Herde, Swed. and Dan. hjord; the Sans. ca‘rdhas, which shows the pre-Teutonic form, means a troop), a number of animals of one kind driven or fed together, usually applied to cattle as “flock” is to sheep, but used also of whales, porpoises, &c., and of birds, as swans, cranes and curlews. A “herd-book” is a book containing the pedigree and other information of any breed of cattle or pigs, like the “flock-book” for sheep or “stud-book” for horses. Formerly the word “herdwick” was applied to the pasture ground under the care of a shepherd, and it is now used of a special hardy breed of sheep in Cumberland and Westmorland. The word “herd” is also applied in a disparaging sense to a company of people, a mob or rabble, as “the vulgar herd.” As the name for a keeper of a herd or flock of domestic animals, the herdsman, it is usually qualified to denote the kind of animal under his protection, as swine-herd, shepherd, &c., but in Ireland, Scotland and the north of England, “herd” alone is commonly used.