A shepherd is someone who looks after sheep. Shepherds usually take the sheep out into fields so that they can graze (eat the grass). In the same way, someone who looks after cows is called a “cowherd”. A "swineherd" looks after pigs and a "goatherd" looks after goats. A herd is a group of animals. "Herding" can also mean making a herd of animals go to another place. A female shepherd is called a “shepherdess”. 