In the pork industry, the term "swine" covers the entire family of pork-producing animals, and the term "pig" is used only for young animals, according to Oklahoma State University. Individual adult members of the swine family are called "hogs."
Sows are female swine, and boars are male swine. Each sow can produce one or two litters of eight to 12 pigs yearly. Pigs under 50 pounds are called nursery pigs. Pigs between 50 and 240 pounds are called growing or finishing pigs. Once a pig reaches 240 pounds, it is considered an adult and called a hog. Fully grown hogs can weigh up to 500 pounds.