Of the major wholesale cuts of beef, this is the most tender. It lies in the middle of the back between the sirloin and the rib, and the muscles in this section do little that could toughen them. The two main muscles in the short loin are the tenderloin and the top loin. The elongated tenderloin muscle (when separated from the bone and the rest of the short loin) can be sold as tenderloin roasts (often labeled chateaubriands), or cut into tournedos or filet mignon steaks. The top loin muscle with the bone attached is called a club steak. When removed from the bone, the same muscle is marketed as New York (or Kansas City) strip steak or Delmonico steak. When the bone is left in and portions of both the tenderloin and top loin muscles are included, the short loin is the source of porterhouse steaks and T-bone steaks.
From The Food Lover's Companion, Fourth edition by Sharon Tyler Herbst and Ron Herbst. Copyright © 2007, 2001, 1995, 1990 by Barron's Educational Series, Inc.