Silverside is a cut of beef from the hindquarter of a cow, just above the leg cut. It gets its name because of the "silverwall" on the side of the cut. This is a long fibrous "skin" which has to be removed for it is too tough to eat.
Silverside is boned out from the top along with the topside and thick flank. It is a 2nd class roasting joint, or may be sliced for minute steak or beef olives, or split in two to produce a salmon-cut. In most parts of the U.S. this cut is known as bottom round, as it comprises the bottom portion of the beef round.