The sirloin steak is a beef steak cut from the rear back portion of the animal, continuing off the short loin from which T-bone, porterhouse, and club steaks are cut.
The sirloin is actually divided into several types of steak. The top sirloin is the most prized of these. The bottom sirloin is less tender, much larger, and is typically what is offered when one just buys sirloin steaks instead of steaks specifically marked top sirloin. The bottom sirloin in turn connects to the sirloin tip roast.