Frequently confused, pork loin and pork tenderloin are actually two different cuts of meat. Pork tenderloin is a long thin cut of pork from the muscle running alongside the backbone. Pork loin, like tenderloin, is long but is much wider in comparison. It is cut from the pig's back, often has a thin layer of fat, and comes bone-in or boneless. Both are on the lean side and more mildly flavored than other cuts of pork.